Computer Maintenance & Troubleshooting

SKILLS DEVELOPMENT PROJECT Ministry of Tertiary Education & Training

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting Notes 211

Developed by Interactive Training Division IDM Computer Studies (Pvt) Ltd. http://www.idm.edu

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting

CHAPTER 1.................................................................................................................4 General System Architecture.........................................................................................4 Structural Organization ..................................................................................................7

CHAPTER 2...............................................................................................................12 Instruction Set Architecture..........................................................................................12 Addressing Modes .......................................................................................................12 Register File .................................................................................................................20

CHAPTER 3...............................................................................................................31 Different Parts of PC....................................................................................................31 Printers.........................................................................................................................46 Bus Designs .................................................................................................................47

PRACTICE LAB1 .....................................................................................................51 OS ................................................................................................................................51

PRACTICE LAB 2 ....................................................................................................54 Software Installation and Preventive Maintenance.....................................................54

PRACTICE LAB 3 ....................................................................................................59 Troubleshooting Tools .................................................................................................59

ASSIGNMENT 1 .......................................................................................................79 Safety from Statis Electricity........................................................................................79

ASSIGNMENT 2 .......................................................................................................81 Computer Performances..............................................................................................81

ASSIGNMENT 3 ......................................................................................................82 Troubleshooting Tools .................................................................................................82

ASSIGNMENT 4 .................................................................................................... 101 VGA Troubleshooting.................................................................................................101

ASSIGNMENT 5 .................................................................................................... 102 Obtaining and Calculating Power Supply Data .........................................................102

CASE STUDY 1 ..................................................................................................... 104 Developed by IDM Interactive Training Division for

Skills Development Project

2

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting Technical Support ......................................................................................................104

CASE STUDY 2 ..................................................................................................... 106 PC Upgrading.............................................................................................................106

Developed by IDM Interactive Training Division for

Skills Development Project

3

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting

CHAPTER 1 General System Architecture Flynn's Classification Flynn uses the stream concept for describing a machine's structure .A stream simply means a sequence of items (data or instructions). Four main types of machine organizations can be found.

SISD (Singe-Instruction stream, Singe-Data stream) SISD corresponds to the traditional mono-processor (von Neumann computer). A single data stream is being processed by one instruction stream

SIMD (Singe-Instruction stream, Multiple-Data streams) In this organization, multiple processing units of the same type process on multiple-data streams. This group is dedicated to array processing machines. Sometimes , vector processors can also be seen as a part of this group.

Developed by IDM Interactive Training Division for

Skills Development Project

4

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting MISD (Multiple-Instruction streams, Singe-Data stream) In case of MISD computers, multiple processing units operate on one singledata stream (Figure c). In practice, this kind of organization has never been used.

MIMD (Multiple-Instruction streams, Multiple-Data streams) This last machine type builds the group for the traditional multi-processors. Several processing units operate on multiple-data streams (Figure d). One example of this group is the SGI Origin 2000

Developed by IDM Interactive Training Division for

Skills Development Project

5

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting

Stored-program Concept Stored-program computer is a term similar to but not synonymous to with the term Von-Neumann Architecture. In a computer of this type programs are stored and executed in main memory -- often but not always after having been loaded in from some storage mechanism. Although this term was often used in computing literature until the 1960s and 1970s it is now rare as it is assumed that all computers are of this type unless stated otherwise.

Von Neumann architecture Von Neumann architectures are computer architectures that use the same storage device for both instructions and data (in contrast to the Harvard architecture). The term originated from First Draft of a Report on the EDVAC (1945), a paper written by the famous mathematician John von Neumann that proposed the stored program concept. The paper was written in connection with plans for a successor machine to the ENIAC and its concepts were discussed by J. Presper Eckert, John Mauchly, Arthur Burks, and others over a period of several months prior to Von Neumann writing the draft report. A von Neumann Architecture computer has five parts: an arithmetic-logic unit, a control unit, a memory, some form of input/output and a bus that provides a data path between these parts. A von Neumann architecture computer performs or emulates the following sequence of steps: 1. Fetch the next instruction from memory at the address in the program counter. 2. Add the length of the instruction to the program counter. 3. Decode the instruction using the control unit. The control unit commands the rest of the computer to perform some operation. The instruction may change the address in the program counter, permitting repetitive operations. The instruction may also change the program counter only if some arithmetic condition is true, giving the effect of a decision, which can be calculated to any degree of complexity by the preceding arithmetic and logic. 4. Go back to step 1. Very few computers have a pure von Neumann architecture. Most computers add another step to check for interrupts, electronic events that could occur at any time. An interrupt resembles the ring of a telephone, calling a person away from some lengthy task. Interrupts let a computer do other things while it waits for events. Von Neumann computers spend a lot of time moving data to and from the memory, and this slows the computer (this problem is called von Neumann bottleneck) So, engineers often separate the bus into two or more busses, usually one for instructions, and the other for data.

Developed by IDM Interactive Training Division for

Skills Development Project

6

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting

Structural Organization CPU Abbreviation of central processing unit, and pronounced as separate letters. The CPU is the brains of the computer. Sometimes referred to simply as the processor or central processor, the CPU is where most calculations take place. In terms of computing power, the CPU is the most important element of a computer system. On large machines, CPUs require one or more printed circuit boards. On personal computers and small workstations, the CPU is housed in a single chip called a microprocessor. Two typical components of a CPU are: •

•

The arithmetic logic unit (ALU), which performs arithmetic and logical operations. The control unit, which extracts instructions from memory and decodes and executes them, calling on the ALU when necessary.

What is the CPU Cache? The cache is a very high speed and very expensive piece of memory, which is used to speed up the memory retrieval process. Due to its expensive CPU's come with a relatively small amount of cache compared with the main system memory. Budget CPU's have even less cache, this is the main way that the top processor manufacturers take the cost out of their budget CPU's. Without the cache memory every time the CPU requested data it would send a request to the main memory which would then be sent back across the memory bus to the CPU. This is a slow process in computing terms. The idea of the cache is that this extremely fast memory would store and data that is frequently accessed and also if possible the data that is around it. This is to achieve the quickest possible response time to the CPU. Its based on playing the percentages. If a certain piece of data has been requested 5 times before, its likely that this specific piece of data will be required again and so is stored in the cache memory. Lets take a library as an example o how caching works. Imagine a large library but with only one librarian (the standard one CPU setup). The first person comes into the library and asks for Lord of the Rings. The librarian goes off follows the path to the bookshelves (Memory Bus) retrieves the book and gives it to the person. The book is returned to the library once its finished with. Now without cache the book would be returned to the shelf. When the next person arrives and asks for Lord of the Rings, the same process happens and takes the same amount of time. If this library had a cache system then once the book was returned it would have been put on a shelf at the librarian’s desk. This way once the second person comes in and asks for Lord of the Rings, the librarian only has to reach down to the shelf and retrieve the book. This significantly reduces the time it takes to retrieve the book. Back to computing this is the same idea, the data in the cache is retrieved Developed by IDM Interactive Training Division for

Skills Development Project

7

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting much quicker. The computer uses its logic to determine which data is the most frequently accessed and keeps them books on the shelf so to speak. That is a one level cache system which is used in most hard drives and other components. CPU's however use a 2 level cache system. The principles are the same. The level 1 cache is the fastest and smallest memory, level 2 cache is larger and slightly slower but still smaller and faster than the main memory. Going back to the library, when Lord of the Rings is returned this time it will be stored on the shelf. This time the library gets busy and lots of other books are returned and the shelf soon fills up. Lord of the Rings hasn't been taken out for a while and so gets taken off the shelf and put into a bookcase behind the desk. The bookcase is still closer than the rest of the library and still quick to get to. Now when the next person comes in asking for Lord of the Rings, the librarian will firstly look on the shelf and see that the book isn't there. They will then proceed to the bookcase to see if the book is in there. This is the same for CPU's. They check the L1 cache first and then check the L2 cache for the data they require .

Developed by IDM Interactive Training Division for

Skills Development Project

8

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting

Main memory Refers to physical mem ory that is internal to the computer. The word main is used to distinguish it from external mass storage devices such as disk drives. Another term for main memory is RAM. The computer can manipulate only data that is in main memory. Therefore, every program you execute and every file you access must be copied from a storage device into main memory. The amount of main memory on a computer is crucial because it determines how many programs can be executed at one time and how much data can be readily available to a program. Because computers often have too little main memory to hold all the data they need, computer engineers invented a technique called swapping, in which portions of data are copied into main memory as they are needed. Swapping occurs when there is no room in memory for needed data. When one portion of data is copied into memory, an equal-sized portion is copied (swapped) out to make room. Now, most PCs come with a minimum of 32 megabytes of main memory. You can usually increase the amount of memory by inserting extra memory in the form of chips.

Secondary memory Secondary memory (or secondary storage) is the slowest and cheapest form of memory. It cannot be processed directly by the CPU. It must first be copied into primary storage (also known as RAM). Secondary memory devices include magnetic disks like hard drives and floppy disks ; optical disks such as CDs and CD ROMs ; and magnetic tapes, which were the first forms of secondary memory.

I/O Units. Short for input/output (pronounced "eye-oh"). The term I/O is used to describe any program, operation or device that transfers data to or from a computer and to or from a peripheral device. Every transfer is an output from one device and an input into another. Devices such as keyboards and mice are input-only devices while devices such as printers are output-only. A writable CD-ROM is both an input and an output device.

Developed by IDM Interactive Training Division for

Skills Development Project

9

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting

Computer Performance Metrics Introduction All performance metrics (measures of performance) are based on system behavior over time. There are three major classes of metrics that can be observed by a user or any other entity outside a system: • • •

Latency or Response Time metrics measure the delay between initiating or requesting some action and the arrival of the result. Throughput or Capacity metrics measure the amount of work done per unit time, or the rate at which new results arrive. Availability metrics measure how much of the time a system is available for normal operation.

A fourth class of metrics, utilization metrics, can only be observed inside a system. Utilization information is vital for understanding and predicting system performance. The remainder of this page discusses each class of metrics in more detail.

Latency Latency or response time metrics are measured in units of (elapsed) time. The definition of latency metric must specify both a start and stop event: when to begin measuring the delay, and when to stop. Some examples of latency metrics: • • • •

The round time between typing a new address in a web browser and the time the requested page is completely displayed. Set up time for a cell phone call might be defined as the delay between pressing the "send" button and hearing the first ring. The time a packet is held by a network router before being forwarded. Delay between receiving an order for an item at an online store and updating the "number in stock" that's reported to other customers.

In many cases, latency is reported or specified as a statistical distribution. For example, a cell phone base station might be required to set up 99.5% of all calls within one second.

Throughput Throughput metrics are measured in units of inverse time. For example: • • • •

transactions completed per minute gigabytes of data written to tape per hour memory accesses per second Megabits of data transmitted per second.

The term bandwidth is often used to describe the theoretical maximum throughput of a date link or other device. For example, a 32-bit wide data bus running at 100 MHz has a bandwidth of 32 billion bits/second. Since all devices impose some overhead in terms of packet headers, gaps between data blocks, or control protocols, the throughput of usable data is always less the bandwidth. Efficiency is defined as the ratio of usable throughput to the bandwidth. For computer networks, where packets Developed by IDM Interactive Training Division for

Skills Development Project

10

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting may be lost or damaged, the term goodput is sometimes used for the arrival rate of undamaged packets. For some applications, throughput metrics may be normalized over some other system characteristic, such as cost or power consumption. It is also a common practice to specify throughout with latency constraint, or visa versa. For example, the Transaction Processing Performance Council TPC-C online transaction processing benchmark reports the throughput of specific mix of transactions, with the requirement that transactions must be completed within fixed time limits, as "tpmC". A second metric "price/tpmC" reports the total cost of the system per transaction.

Availability The term availability is used to describe the fraction of time a system is available. For example, if an inventory database is down for an hour a day, it has an availability of about 0.96. However, the availability metric alone doesn't tell the whole story. For example, if the same inventory database went down for 10 milliseconds each second, it would have an availability of 0.99 but would probably be useless for any practical purpose. Therefore, the reliability metric is used to report the mean time between failures (MTBF), which indicates on average, the period a system is usable. A related metric is mean time to repair (MTTR), which quantifies how long it takes to recover from a failure.

Utilization The fraction of time that a system component, such as CPU, disk, or data link, is active is its utilization. It follows from this definition that utilization values range between 0 and 1. The maximum throughput of a system (its throughput capacity) is reached when the busiest component reaches a utilization of 1. As a practical matter, response time increases rapidly as utilization approaches 100%, so that many systems are designed to keep utilization below some threshold such as 70% or 80%. The path length of a device for specific workload is the device utilization divided by the throughput. The path length has units of time and it indicates how much time the device needs to process one unit of work, such as a transaction, packet, etc. Path length is short for "code path length" or the number of instructions required to complete a specific task. As CPU design has progressed, the introduction of caches, virtual memory, pipelining, and concurrent execution of multiple instructions have all made the relationship between instruction count and CPU time less predictable. For current technology, it's better to think of path length as "CPU time per transaction." Knowledge of utilization and path length is required to do any sort of predictive performance modeling. Therefore, most processors and operating systems incorporate a facility for measuring utilization.

Developed by IDM Interactive Training Division for

Skills Development Project

11

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting

CHAPTER 2 Instruction Set Architecture The instruction set architecture of a processor serves as the interface between hardware and software. Although perfected closely resemble load instructions, the desired semantics and actions are quite different. This section discusses these semantic and functional issues.

RISC Pronounced risk, acronym for reduced instruction set computer, a type of microprocessor that recognizes a relatively limited number of instructions. Until the mid-1980s, the tendency among computer manufacturers was to build increasingly complex CPUs that had ever-larger sets of instructions. At that time, however, a number of computer manufacturers decided to reverse this trend by building CPUs capable of executing only a very limited set of instructions. One advantage of reduced instruction set computers is that they can execute their instructions very fast because the instructions are so simple. Another, perhaps more important advantage, is that RISC chips require fewer transistors, which makes them cheaper to design and produce. Since the emergence of RISC computers, conventional computers have been referred to as CISCs (complex instruction set computers). There is still considerable controversy among experts about the ultimate value of RISC architectures. Its proponents argue that RISC machines are both cheaper and faster, and are therefore the machines of the future. Skeptics note that by making the hardware simpler, RISC architectures put a greater burden on the software. They argue that this is not worth the trouble because conventional microprocessors are becoming increasingly fast and cheap anyway. To some extent, the argument is becoming moot because CISC and RISC implementations are becoming more and more alike. Many of today's RISC chips support as many instructions as yesterday's CISC chips. And today's CISC chips use many techniques formerly associated with RISC chips.

CISC Pronounced sisk, and stands for complex instruction set computer. Most personal computers use a CISC architecture, in which the CPU supports as many as two hundred instructions. An alternative architecture, used by many workstations and also some personal computers, is RISC (reduced instruction set computer), which supports fewer instructions.

Addressing Modes Developed by IDM Interactive Training Division for

Skills Development Project

12

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting Register A, special, high-speed storage area within the CPU. All data must be represented in a register before it can be processed. For example, if two numbers are to be multiplied, both numbers must be in registers, and the result is also placed in a register. (The register can contain the address of a memory location where data is stored rather than the actual data itself.) The number of registers that a CPU has and the size of each (number of bits) help determine the power and speed of a CPU. For example a 32-bit CPU is one in which each register is 32 bits wide. Therefore, each CPU instruction can manipulate 32 bits of data. Usually, the movement of data in and out of registers is completely transparent to users, and even to programmers. Only assembly language programs can manipulate registers. In high-level languages, the compiler is responsible for translating highlevel operations into low-level operations that access registers.

Register Addressing Diagram

Developed by IDM Interactive Training Division for

Skills Development Project

13

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting • • • •

Similar to direct addressing Only difference is that the address field refers to a register rather than a main memory address. Advantage: • Only a small address field is needed in the instruction • No memory references are required. If the register addressing is heavily used in an instruction set, this implies that the CPU registers will be heavily used. • Operand is contained in the register named in the address field • If R is the register name then EA = R • Since there is a limited number of registers, then a very small address field is needed o Shorter instructions o Faster instruction fetch • e.g. ADD rA o Look into register A for operand o Add content of register A to accumulator o Acc+(rA)? ? Acc • • • • • •

No main memory access Very fast execution Very limited address space (= # registers) Multiple registers may help performance Conceptually similar to direct addressing… But operations on registers require fewer clock cycles

Immediate Addressing Diagram

• •

Operand is actually present in the instruction No memory reference other the instruction fetch is required to obtain the operand.

• • • •

The value of address field is the operand No memory reference to fetch data Fast Limited range

Developed by IDM Interactive Training Division for

Skills Development Project

14

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting Direct Addressing Diagram

• • • • • • •

Address field contains the effective address of the operand. Requires only one memory reference and no special calculation The value of address field is the address of the operand If A is the value then (A) denotes the value contained in the memory cell with address A Single memory reference to access data No additional calculations to work out effective address Limited address space

Developed by IDM Interactive Training Division for

Skills Development Project

15

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting Indirect Addressing Diagram

•

To have the address field refer to the address of a word in memory, this in turn contains a full-length address of the operand. • Advantage: is that for a word length of N, an address space of 2 power of N is now available. • Disadvantage: is that instruction execution requires two memory references to fetch the operand: one to get its address and a second to get its value. • The memory cell referenced by the address field contains the address of (i.e., the pointer to) the operand • If A is the value of the address field, then EA is the Effective Address in memory of the operand and is EA=(A) • Large address space • 2n addressable cells where n is the number of bits in the address field • May be nested, multilevel, cascaded • Multiple memory accesses to find operand • Hence slower

Indexed Addressing • • • • •

A is the base value R contains the displacement EA = A + (R) Good for accessing all array cells in sequence First access address EA = A + (R), then increment the content of R, and repeat

Developed by IDM Interactive Training Division for

Skills Development Project

16

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting

Operations Arithmetic and logical unit An arithmetic and logical unit (ALU) is one of the core components of all central processing units. It is capable of calculating the results of a wide variety of common computations. The most common available operations are the integer arithmetic operations of addition, subtraction, and multiplication, the bitwise logic operations of AND, NOT, OR, and XOR, and various shift operations. Typically, a standard ALU does not handle integer division nor any floating point operations. For these calculations a separate component, such as a divider or floating point unit (FPU), is often used, although it is also possible that a microcode program may use the ALU to emulate these operations. The ALU takes as inputs the data to be operated on and a code from the control unit indicating which operation to perform, and for output provides the result of the computation. In some designs it may also take as input and output a set of condition codes, which can be used to indicate cases such as carry-in or carry-out, overflow, or other statuses.

Processor operations Processor Operations helps operators manage more systems with greater efficiency. One operator, in one location, can initialize, configure, monitor, shut down, and recover multiple systems -- both local and remote -- and respond to a variety of detected conditions. The operator, using one standard interface, can do all that across multiple types of systems. Automated routines for frequently used functions speed the work of skilled operators and assist less experienced operators to become more productive. Processor Operations supports monitoring and control functions for any of the following processors: • •

zSeries and 390-CMOS processors All CMOS processors supporting Operations Command Facility (OCF) that are not part of the above processor families are supported by processor operations with limited functionality

SA OS/390 processor operations supports logical partitioning of any of these processors that also support logical partitioning. The operating systems that processor operations supports on the target systems are z/OS, OS/390, MVS, VM, VSE, and Linux for zSeries. Processor operations monitors and controls processor hardware operations. It provides a connection from a focal point processor to a target processor. With NetView on the focal point processor, processor operations automates operator and system consoles for monitoring and recovering target processors.

Developed by IDM Interactive Training Division for

Skills Development Project

17

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting Processor operations allows you to power on and off multiple target processors and reset them. You can perform IPLs, set the time of day clocks, respond to messages, monitor status, and detect and resolve wait states.

Control Flow Architecture Control dominated architecture design is significantly different from data-flow. Very few tools are offered on the market to address this aspect of design. Control flow applications are driven by a set of commands that have to be interpreted. Each command is a sequence of control and data, and may imply reading or writing complex data structures and executing a specific algorithm. The computation performed may be data dependent. This includes handshaking with the environment, data dependent loops and fast reaction to interrupts. In complex system, data flow components are almost always mixed with control flow components, at least at top level. Whenever a systems includes control flow elements, a simple design strategy is to use the control part as the "skeletton" of the architecture, and to design the data flow modules as components (dedicated coprocessors). templates is possible. The specific template used for control-flow processor synthesis is based on a hierarchy of complex controllers were data-flow processors can be introduced as coprocessors at any level.

The Instruction Set Architecture • The Instruction Set Architecture (ISA) view of a machine corresponds to the machine and assembly language levels. • A compiler translates a high level language, which is architecture Independent, into assembly language, which is architecture dependent. • An assembler translates assembly language programs into executable Binary codes. • For fully compiled languages like C and Fortran, the binary codes Are executed directly by the target machine. Java stops the translation At the byte code level. The Java virtual machine, which is at the assembly language level, interprets the byte codes (hardware implementations of the JVM also exist, in which Java byte codes are executed directly.)

Developed by IDM Interactive Training Division for

Skills Development Project

18

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting

Basic Non Pipe Lined CPU Architecture PIPE LINE A Pipeline is a series of stages, where some work is done at each stage. The work is not finished until it has passed through all stages. Pipelining is an implementation technique in which multiple instructions are overlapped in execution. Today, Pipelining is key to making processors fast. A pipeline is like an assembly line: in both, each step completes one piece of the whole job. Workers on a car assembly line perform small tasks, such as installing seat covers. The power of the assembly line comes from many cars per day. On a well-balanced assembly line, a new car exits the line in the time it takes to perform one of the many steps. Note that the assembly line does not reduce the time it takes to complete an individual car; it increases the number of cars being built simultaneously and thus the rate at which the cars are started and completed. There are two types of pipelines, Instructional pipeline where different stages of an instruction fetch and execution are handled in a pipeline and Arithmetic pipeline where different stages of an arithmetic operation are handled along the stages of a pipeline.

A Simple Non-Pipelined CPU A simple, non-pipelined CPU also executes instructions in discrete steps or cycles. Although the quantity and function of each step varies from machine to machine, the basic ideas remain the same. Figure 1 shows the basic steps of instruction execution in a non-pipelined, “LOAD/STORE” CPU. This simple CPU is taken from the pedagogical DLX architecture, proposed by Hennessy and Patterson in Computer Architecture A Quantitative Approach (Morgan Kaufmann, 1990). A “LOAD/STORE” CPU performs all of its operations on register operands. The register operands are read from memory by “LOAD” instructions and are written back to memory by “STORE” instructions.

Superpipelined Processors In contrast to a superscalar processor, a superpipelined one has split the main computational pipeline into more stages. Each stage is simpler (does less work) and thus the clock speed can be increased. However the latency, measured in clock cycles, for any instruction to complete has increased from 4 cycles in early RISC processors to 8 or more. Benefit The major benefit of superpipelining is the increase in the number of instructions which can be in the pipeline at one time and hence the level of parallelism. Drawbacks The larger number of instructions "in flight" (ie in some part of the pipeline) at any time, increases the potential for data dependencies to introduce stalls. Simulation studies have suggested that a pipeline depth of more than 8 stages tends to be counter-productive.

Developed by IDM Interactive Training Division for

Skills Development Project

19

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting Note that some recent processors, eg the MIPS R10000, can be described as both superscalar - they have multiple processing units - and superpipelined - there are more than 5 stages in the pipeline.

Register File The Register File is the highest level of the memory hierarchy. In a very simple processor, it consists of a single memory location - usually called an accumulator. The result of ALU operations was stored here and could be re-used in a subsequent operation or saved into memory. In a modern processor, it's considered necessary to have at least 32 registers for integer values and often 32 floating point registers as well. Thus the register file is a small, addressable memory at the top of the memory hierarchy. It's visible to programs (which address registers directly), so that the number and type (integer or floating point) of registers is part of the instruction set architecture (ISA).

Register File Capacity A modern processor will have at least 32 integer registers each capable of storing a word of 32 (or, more recently, 64) bits. A processor with floating point capabilities will generally also provide 32 or more floating point registers, each capable of holding a double precision floating point word. These registers are used by programs as temporary storage for values which will be needed for calculations. Because the registers are "closest" to the processor in terms of access time - able to supply a value within a single clock cycle - an optimising compiler for a high level language will attempt to retain as many frequently used values in the registers as possible. Thus the size of the register file is an important factor in the overall speed of programs. Earlier processors with fewer than 32 registers (eg early members of the x86 family) severely hampered the ability of the compiler to keep frequently referenced values close to the processor.

Stacks Hardware implementation of stacks has the obvious advantage that it can be much faster than software management. In machines that refer to the stack with a large percentage of instructions, this increased efficiency is vital to maintaining high system performance. While any software method of handling stacks can be implemented in hardware, the generally practiced hardware implementation is to reserve contiguous locations of memory with a stack pointer into that memory. Usually the pointer is a dedicated hardware register that can be incremented or decremented as required to push and pop elements. Sometimes a capability is provided to add an offset to the stack pointer to nondestructively access the first few elements of the stack without requiring successive pop operations. Often times the stack is resident in the same memory devices as the program. Sometimes, in the interest of increased efficiency, the stacks reside in their own memory devices. Another approach that may be taken to building stacks in hardware is to use large shift registers. Each shift register is a long chain of registers with one end of the Developed by IDM Interactive Training Division for

Skills Development Project

20

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting chain being visible as a single bit at the top of stack. 32 such shift registers of N bits each may be placed side-by-side to form a 32 bit wide by N element stack. While this approach has not been practical in the past, VLSI stack machines may find this a viable alternative to the conventional register pointing into memory implementation.

Register Special, high-speed storage area within the CPU. All data must be represented in a register before it can be processed. For example, if two numbers are to be multiplied, both numbers must be in registers, and the result is also placed in a register. (The register can contain the address of a memory location where data is stored rather than the actual data itself.) The number of registers that a CPU has and the size of each (number of bits) help determine the power and speed of a CPU. For example a 32-bit CPU is one in which each register is 32 bits wide. Therefore, each CPU instruction can manipulate 32 bits

of data. Usually, the movement of data in and out of registers is completely transparent to users, and even to programmers. Only assembly language programs can manipulate registers. In high-level languages, the compiler is responsible for translating highlevel operations into low-level operations that access registers.

Register Renaming There are many solutions to resolve a pipeline stall. One way is to simply add more registers to the CPU, which should give us more quick storage spaces. That way, we could store all the values we need within the registers so the CPU would not have to fetch data directly from memory. As with the case of two instructions trying to write to a single accumulator, we could eliminate the stall if we added another accumulator. However, adding more registers is expensive. In addition, a complex program can fill up all the registers in our CPU within a short period of time. Many CPU manufacturers use register renaming instead of adding more registers. In this way, there are more registers available during program execution. Register renaming dynamically associates physical registers to logical registers.i This is usually done during the execution phase where an Address Generator Unit (AGU) within the Arithmetic Logic Unit (ALU) assigns the executed data or instruction into a specific register, cache or memory.

Developed by IDM Interactive Training Division for

Skills Development Project

21

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting Fetch Execute Cycle The sequence of actions that a central processing unit performs to execute each machine code instruction in a program. At the beginning of each cycle the CPU presents the value of the program counter on the address bus. The CPU then fetches the instruction from main memory (possibly via a cache and/or a pipeline) via the data bus into the instruction register. From the instruction register, the data forming the instruction is decoded and passed to the control unit which sends a sequence of control signals to the relevant function units of the CPU to perform the actions required by the instruction such as reading values from registers, passing them to the ALU to add them together and writing the result back to a register. The program counter is then incremented to address the next instruction and the cycle is repeated. • • • • • • • •

Extract the instruction from Memory calculate the address of the next instruction, by advancing the PC decode the opcode calculate the address of the operand (if any) extract the operand from memory execute calculate the address of the result store the result in memory

Microprogramming The microprogram is the essential part of the computer which allows the interaction between hardware and software. In many processors, the microprogram executes machine code instructions directly on the hardware, providing a final level of interpretation between machine language instructions and the basic memory and arithmetic operations performed by the hardware. However, some new architectures do not implement a microprogram. Instead, operations in the digital logic level are run directly by software. In this project, I will examine microprogramming in terms of its role as the intersection of hardware and software, and in doing so, compare and contrast microinstruction-rich and microinstruction-deficient architectures, and examine various new approaches to hardware/software interaction.

Developed by IDM Interactive Training Division for

Skills Development Project

22

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting The Hard-Wired Control Unit

This figure is a block diagram showing the internal organization of a hard-wired control unit for our simple computer. Input to the controller consists of the 4-bit opcode of the instruction currently contained in the Instruction Register and the negative flag from the accumulator. The controller's output is a set of 16 control signals that go out to the various registers and to the memory of the computer, in addition to a HLT signal that is activated whenever the leading bit of the op-code is one. The controller is composed of the following functional units: A ring counter, an instruction decoder, and a control matrix. The ring counter provides a sequence of six consecutive active signals that cycle continuously. Synchronized by the system clock, the ring counter first activates its T0 line, then its T1 line, and so forth. After T5 is active, the sequence begins again with T0.

Developed by IDM Interactive Training Division for

Skills Development Project

23

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting

Memory Hierarchy and I/O Techniques Memory Hierarchy

Memory Hierarchy We first illustrate the issues involved in optimizing memory system performance on multiprocessors, and define the terms that are used in this paper. True sharing cache misses occur whenever two processors access the same data word. True sharing requires the processors involved to explicitly synchronize with each other to ensure program correctness. A computation is said to have temporal locality if it re-uses much of the data it has been accessing; programs with high temporal locality tend to have less true sharing. The amount of true sharing in the program is a critical factor for performance on multiprocessors; high levels of true sharing and synchronization can easily overwhelm the advantage of parallelism. It is important to take synchronization and sharing into consideration when deciding on how to parallelize a loop nest and how to assign the iterations to processors. Consider the code shown in Figure 1(a). While all the iterations in the first two-deep loop nest can run in parallel, only the inner loop of the second loop nest is parallelizable. To minimize synchronization and sharing, we should also parallelize only the inner loop in the first loop nest. By assigning the ith iteration in each of the inner loops to the same processor, each processor always accesses the same rows of the arrays throughout the entire computation. Figure 1(b) shows the data accessed by each processor in the case where each processor is assigned a block of rows. In this way, no interprocessor communication or synchronization is necessary.

Developed by IDM Interactive Training Division for

Skills Development Project

24

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting Main Memory The storage device used by a computer to hold the currently executing program and its working data. A modern computer's main memory is built from random access memory integrated circuits. In the old days ferrite core memory was one popular form of main memory, leading to the use of the term "core" for main memory. Computers have several other sorts of memory, distinguished by their access time, storage capacity, cost, and the typical lifetime or rate of change of the data they hold. Registers in the CPU are fast, few, expensive and typically change every few machine instructions. Other kinds are cache, PROM, magnetic disk (which may be used for virtual memory), and magnetic tape.

Cache Memory a special high-speed storage mechanism. It can be either a reserved section of main memory or an independent high-speed storage device. Two types of caching are commonly used in personal computers: memory caching and disk caching. A memory cache, sometimes called a cache store or RAM cache, is a portion of memory made of high-speed static RAM (SRAM) instead of the slower and cheaper dynamic RAM (DRAM) used for main memory. Memory caching is effective because most programs access the same data or instructions over and over. By keeping as much of this information as possible in SRAM, the computer avoids accessing the slower DRAM. Some memory caches are built into the architecture of microprocessors. The Intel 80486 microprocessor, for example, contains an 8K memory cache, and the Pentium has a 16K cache. Such internal caches are often called Level 1 (L1) caches. Most modern PCs also come with external cache memory, called Level 2 (L2) caches. These caches sit between the CPU and the DRAM. Like L1 caches, L2 caches are composed of SRAM but they are much larger. Disk caching works under the same principle as memory caching, but instead of using high-speed SRAM, a disk cache uses conventional main memory. The most recently accessed data from the disk (as well as adjacent sectors) is stored in a memory buffer. When a program needs to access data from the disk, it first checks the disk cache to see if the data is there. Disk caching can dramatically improve the performance of applications, because accessing a byte of data in RAM can be thousands of times faster than accessing a byte on a hard disk. When data is found in the cache, it is called a cache hit, and the effectiveness of a cache is judged by its hit rate. Many cache systems use a technique known as smart caching, in which the system can recognize certain types of frequently used data. The strategies for determining which information should be kept in the cache constitute some of the more interesting problems in computer science.

Developed by IDM Interactive Training Division for

Skills Development Project

25

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting Secondary Memory Secondary memory (or secondary storage) is the slowest and cheapest form of memory. It cannot be processed directly by the CPU. It must first be copied into primary storage (also known as RAM ). Secondary memory devices include magnetic disks like hard drives and floppy disks ; optical disks such as CDs and CDROMs ; and magnetic tapes, which were the first forms of secondary memory.

I/O Methods The original MemoryObject class has two I/O methods: the read and write methods. These methods read and write to the memory object directly. With the integration of file system caching, these methods are no longer sufficient. At least two sets of I/O methods are required. The first set of I/O methods does I/O directly from and to memory objects like the original read and write methods. The revised virtual memory management system uses these methods to read data into main memory and write data out of main memory. The second set of I/O methods supports file system I/O. These methods do I/O through a memory object cache if a memory object is cached. In the revised virtual memory management system, the original read and write methods of the MemoryObject class has been renamed rawRead and rawWrite. The rawRead and rawWrite methods do I/O directly from and to memory objects. Then, new read and write methods are defined. If a memory object is cached, these methods invoke the cacheRead and cacheWrite methods of the memory object's memory object cache. If a memory object is not cached, these methods invoke the memory object's rawRead and rawWrite methods.

Developed by IDM Interactive Training Division for

Skills Development Project

26

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting

Input / Output (I/O) I/O Modules It is not possible to simply connect I/O devices directly to the system bus for several reasons. o

There are many different types of device, each with a different method of operation, e.g. monitors, disk drives, keyboards. It is impracticable for a CPU to be aware of the operation of every type of device, particularly as new devices may be designed after the CPU has been produced. o The data transfer rate of most peripherals is much slower than that of the CPU. The CPU cannot communicate directly with such devices without slowing the whole system down. o Peripherals will often use different data word sizes and formats than the CPU.

For this reason a computer system must use I/O modules, components which interface between the CPU and the peripherals. An I/O module has several functions. o o o o o

Controlling the peripheral and synchronising its operation with that of the CPU Communicating with the CPU through the system bus Communicating with the peripheral through an I/O interface Buffering data Error detection

An I/O module consists of several parts. o o o o

A connection to the system bus Some control logic A data buffer An interface to the peripheral(s)

We shall consider two main areas. o o

The strategy by which I/O modules communicate with the CPU. The interface between I/O modules and the device(s) connected to them.

Developed by IDM Interactive Training Division for

Skills Development Project

27

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting Programmed I/O The simplest strategy for handling communication between the CPU and an I/O module is programmed I/O. Using this strategy, the CPU is responsible for all communication with I/O modules, by executing instructions which control the attached devices, or transfer data. For example, if the CPU wanted to send data to a device using programmed I/O, it would first issue an instruction to the appropriate I/O module to tell it to expect data. The CPU must then wait until the module responds before sending the data. If the module is slower than the CPU, then the CPU may also have to wait until the transfer is complete. This can be very inefficient. Another problem exists if the CPU must read data from a device such as a keyboard. Every so often the CPU must issue an instruction to the appropriate I/O module to see if any keys have been pressed. This is also extremely inefficient. Consequently this strategy is only used in very small microprocessor controlled devices.

Interrupt Driven I/O A more common strategy is to use interrupt driven I/O. This strategy allows the CPU to carry on with its other operations until the module is ready to transfer data. When the CPU wants to communicate with a device, it issues an instruction to the appropriate I/O module, and then continues with other operations. When the device is ready, it will interrupt the CPU. The CPU can then carry out the data transfer as before. This also removes the need for the CPU to continually poll input devices to see if it must read any data. When an input device has data, then the appropriate I/O module can interrupt the CPU to request a data transfer. An I/O module interrupts the CPU simply by activating a control line in the control bus. The sequence of events is as follows. 1. 2. 3. 4. 5.

The I/O module interrupts the CPU. The CPU finishes executing the current instruction. The CPU acknowledges the interrupt. The CPU saves its current state. The CPU jumps to a sequence of instructions which will handle the interrupt.

The situation is somewhat complicated by the fact that most computer systems will have several peripherals connected to them. This means the computer must be able to detect which device an interrupt comes from, and to decide which interrupt to handle if several occur simultaneously. This decision is usually based on interrupt priority. Some devices will require response from the CPU more quickly than others, for example, an interrupt from a disk drive must be handled more quickly than an interrupt from a keyboard.

Developed by IDM Interactive Training Division for

Skills Development Project

28

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting Many systems use multiple interrupt lines. This allows a quick way to assign priorities to different devices, as the interrupt lines can have different priorities. However, it is likely that there will be more devices than interrupt lines, so some other method must be used to determine which device an interrupt comes from. Most systems use a system of vectored interrupts. When the CPU acknowledges an interrupt, the relevant device places a word of data (a vector) on the data bus. The vector identifies the device which requires attention, and is used by the CPU to look up the address of the appropriate interrupt handing routine.

DMA (Direct Memory Access) Although interrupt driven I/O is much more efficient than program controlled I/O, all data is still transferred through the CPU. This will be inefficient if large quantities of data are being transferred between the peripheral and memory. The transfer will be slower than necessary, and the CPU will be unable to perform any other actions while it is taking place. Many systems therefore use an additional strategy, known as direct memory access (DMA). DMA uses an additional piece of hardware - a DMA controller. The DMA controller can take over the system bus and transfer data between an I/O module and main memory without the intervention of the CPU. Whenever the CPU wants to transfer data, it tells the DMA controller the direction of the transfer, the I/O module involved, the location of the data in memory, and the size of the block of data to be transferred. It can then continue with other instructions and the DMA controller will interrupt it when the transfer is complete. The CPU and the DMA controller cannot use the system bus at the same time, so some way must be found to share the bus between them. One of two methods is normally used. Burst mode The DMA controller transfers blocks of data by halting the CPU and controlling the system bus for the duration of the transfer. The transfer will be as quick as the weakest link in the I/O module/bus/memory chain, as data does not pass through the CPU, but the CPU must still be halted while the transfer takes place.

Developed by IDM Interactive Training Division for

Skills Development Project

29

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting Cycle Stealing The DMA controller transfers data one word at a time, by using the bus during a part of an instruction cycle when the CPU is not using it, or by pausing the CPU for a single clock cycle on each instruction. This may slow the CPU down slightly overall, but will still be very efficient. Process of Cycle Stealing • Cycle stealing is a strategy whereby DMA module uses the system bus to move data between the I/O module/external devices at times when the CPU is not using the bus. • During the decode cycle of the fetch-decode-execute cycle the BUS is not in use thus the DMA module “steals” or takes control of the bus. • The DMA module transfers one word and returns control to CPU. • It is not an interrupt because the CPU does not change state; it does not jump to any special service routine; it is just paused for one or more cycles.

Developed by IDM Interactive Training Division for

Skills Development Project

30

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting

CHAPTER 3 Different Parts of PC Computer Monitor The computer monitor is an output device that is part of your computer's display system. A cable connects the monitor to a video adapter (video card) that is installed in an expansion slot on your computer’s motherboard. This system converts signals into text and pictures and displays them on a TV-like screen (the monitor). The computer sends a signal to the video adapter, telling it what character, image or graphic to display. The video adapter converts that signal to a set of instructions that tell the display device (monitor) how to draw the image on the screen.

Cathode Ray tube The CRT, or Cathode Ray Tube, is the "picture tube" of your monitor. Although it is a large vacuum tube, it's shaped more like a bottle. The tube tapers near the back where there's a negatively charged cathode, or "electron gun". The electron gun shoots electrons at the back of the positively charged screen, which is coated with a phosphorous chemical. This excites the phosphors causing them to glow as individual dots called pixels (picture elements). The image you see on the monitor's screen is made up of thousands of tiny dots (pixels). If you've ever seen a child's LiteBrite toy, then you have a good idea of the concept. The distance between the pixels has a lot to do with the quality of the image. If the distance between pixels on a monitor screen is too great, the picture will appear "fuzzy", or grainy. The closer together the pixels are, the sharper the image on screen. The distance between pixels on a computer monitor screen is called its dot pitch and is measured in millimeters. (see sidebar). You should try to get a monitor with a dot pitch of .28 mm or less. There are a couple of electromagnets (yokes) around the collar of the tube that actually bend the beam of electrons. The beam scans (is bent) across the monitor from left to right and top to bottom to create, or draw the image, line by line. The number of times in one second that the electron gun redraws the entire image is called the refresh rate and is measured in Hertz (Hz). If the scanning beam hits each and every line of pixels, in succession, on each pass, then the monitor is known as a non-interlaced monitor. A non-interlaced monitor is preferred over an interlaced monitor. The electron beam on an interlaced monitor scans the odd numbered lines on one pass, then scans the even lines on the second pass. This results in an almost imperceivable flicker that can cause eye-strain. This type of eye-strain can result in blurred vision, sore eyes, headaches and even nausea. Don't buy an interlaced monitor, they can be a real pain in the ... ask your optometrist. Interlaced computer monitors are getting harder to find (good!), but they are still out there, so keep that in mind when purchasing a monitor and watch out for that "steal of a deal". Developed by IDM Interactive Training Division for

Skills Development Project

31

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting

Video Technologies Video technologies differ in many different ways. However, the major 2 differences are resolution and the number of colors it can produce at those resolutions .

Resolution Resolution is the number of pixels that are used to draw an image on the screen. If you could count the pixels in one horizontal row across the top of the screen, and the number of pixels in one vertical column down the side, that would properly describe the resolution that the monitor is displaying. It’s given as two numbers. If there were 800 pixels across and 600 pixels down the side, then the resolution would be 800 X 600. Multiply 800 times 600 and you’ll get the number of pixels used to draw the image (480,000 pixels in this example). A monitor must be matched with the video card in the system. The monitor has to be capable of displaying the resolutions and colors that the adapter can produce. It works the other way around too. If your monitor is capable of displaying a resolution of 1,024 X 768 but your adapter can only produce 640 X 480, then that’s all you’re going to get. When we talk about the different technologies, we’re talking about the video card and monitor that make up that display system. Also, standards describe the basic number of colors and resolutions for each technology, but individual manufacturers always take liberties, providing options and enhancements that are designed to make their product more appealing to the end user. This is, of course, how new standards come about.

Monochrome Monochrome monitors are very basic displays that produce only one color. The basic text mode in DOS is 80 characters across and 25 down. When graphics were first introduced, they were fairly rough by today’s standards, and you had to manually type in a command to change from text mode to graphics mode. A company called Hercules Graphics developed a video adapter that could do this for you. Not only could it change from text to graphics, but it could do it on the fly whenever the application required it. Today’s adapters still basically use the same methods .

Developed by IDM Interactive Training Division for

Skills Development Project

32

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting CGA/EGA The Color Graphics Adapter (CGA) introduced color to the personal computer. In APA mode it can produce a resolution of 320 X 200 and has a palette of 16 colors but can only display 4 at a time. With the introduction of the IBM Enhanced Graphics Adapter (EGA), the proper monitor was capable of a resolution of 640 X 350 pixels and could display 16 colors from a palette of 64.

VGA Up until VGA, colors were produced digitally. Each electron beam could be either on or off. There were three electron guns, one for each color, red, green and blue (RGB). This combination could produce 8 colors. By cutting the intensity of the beam in half, you could get 8 more colors for a total of 16. IBM came up with the idea of developing an analog display system that could produce 64 different levels of intensity. Their new Video Graphics Array adapter was capable of a resolution of 640 X 480 pixels and could display up to 256 colors from a palette of over 260,000. This technology soon became the standard for almost every video card and monitor being developed.

SVGA Once again, manufacturers began to develop video adapters that added features and enhancements to the VGA standard. Super-VGA is based on VGA standards and describes display systems with several different resolutions and a varied number of colors. When SVGA first came out it could be defined as having capabilities of 800 X 600 with 256 colors or 1024 X 768 with 16 colors. However, these cards and monitors are now capable of resolutions up to 1280 X 1024 with a palette of more than 16 million colors.

XGA Extended Graphics Array was developed by IBM. It improved upon the VGA standard (also developed by IBM) but was a proprietary adapter for use in Micro Channel Architecture expansion slots. It had its own coprocessor and bus-mastering ability, which means that it had the ability to execute instructions independent of the CPU. It was also a 32-bit adapter capable of increased data transfer speeds. XGA allowed for better performance, could provide higher resolution and more colors than the VGA and SVGA cards at the time. However, it was only available for IBM machines. Many of these features were later incorporated by other video card manufacturers.

Developed by IDM Interactive Training Division for

Skills Development Project

33

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting Video Adapter A board that plugs into a personal computer to give it display capabilities. The display capabilities of a computer, however, depend on both the logical circuitry (provided in the video adapter) and the display monitor. A monochrome monitor, for example, cannot display colors no matter how powerful the video adapter. Many different types of video adapters are available for PCs. Most conform to one of the video standards defined by IBM or VESA. Each adapter offers several different video modes. The two basic categories of video modes are text and graphics. In text mode, a monitor can display only ASCII characters. In graphics mode, a monitor can display any bit-mapped image. Within the text and graphics modes, some monitors also offer a choice of resolutions. At lower resolutions a monitor can display more colors. Modern video adapters contain memory, so that the computer's RAM is not used for storing displays. In addition, most adapters have their own graphics coprocessor for performing graphics calculations. These adapters are often called graphics accelerators. Like most parts of the PC, the video card had very humble beginnings--it was only responsible for taking what the processor produced as output and displaying it on the screen. Early on, this was simply text, and not even color at that. Video cards today are much more like coprocessors; they have their own intelligence and do a lot of processing that would otherwise have to be done by the system processor. This is a necessity due to the enormous increase both in how much data we send to our monitors today, and the sophisticated calculations that must be done to determine what we see on the screen. This is particularly so with the rise of graphical operating systems, and 3D computing. The video card in your system plays a significant role in the following important aspects of your computer system: •

Performance: The video card is one of the components that has an impact on system performance. For some people (and some applications) the impact is not that significant; for others, the video card's quality and efficiency can impact on performance more than any other component in the PC! For example, many games that depend on a high frame rate (how many times per second the screen is updated with new information) for smooth animation, are impacted far more by the choice of video card than even by the choice of system CPU.

•

Software Support: Certain programs require support from the video card. The software that normally depends on the video card the most includes games and graphics programs. Some programs (for example 3D-enhanced games) will not run at all on a video card that doesn't support them.

•

Reliability and Stability: While not a major contributor to system reliability, choosing the wrong video card can cause problematic system behavior. In particular, some cards or types of cards are notorious for having unstable drivers, which can cause a host of difficulties.

Developed by IDM Interactive Training Division for

Skills Development Project

34

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting •

Comfort and Ergonomics: The video card, along with the monitor, determines the quality of the image you see when you use your PC. This has an important impact on how comfortable the PC is to use. Poor quality video cards don't allow for sufficiently high refresh rates, causing eyestrain and fatigue.

This section discusses the video card and its characteristics in detail, including its components, performance factors, video modes and resolution, and multimedia. I also discuss different memory technologies used in video cards today.

Color Graphics Adapter (CGA) The first mainstream video card to support color graphics on the PC was IBM's Color Graphics Adapter (CGA) standard. The CGA supports several different modes; the highest quality text mode is 80x25 characters in 16 colors. Graphics modes range from monochrome at 640x200 (which is worse than the Hercules card) to 16 colors at 160x200. The card refreshes at 60 Hz. Note that the maximum resolution of CGA is actually significantly lower than MDA: 640x200. These dots are accessible individually when in a graphics mode but in text each character was formed from a matrix that is 8x8, instead of the MDA's 9x14, resulting in much poorer text quality. CGA is obsolete, having been replaced by EGA.

Hercules Graphics Card One weakness of the original MDA display was that it did not support graphics of any kind. A company named Hercules created in the early 80s an MDA-compatible video card that supported monochrome graphics in addition to the standard text modes. The Hercules card was actually a very widely-accepted standard in the mid-80s; eventually Hercules clones even appeared on the market. Support for the card was included in popular software packages such as Lotus 1-2-3 to allow the display of graphs and charts on the computer screen. It has of course been replaced by later, color, graphics adapters.

Enhanced Graphics Adapter (EGA) IBM's next standard after CGA was the Enhanced Graphics Adapter or EGA. This standard offered improved resolutions and more colors than CGA, although the capabilities of EGA are still quite poor compared to modern devices. EGA allowed graphical output up to 16 colors (chosen from a palette of 64) at screen resolutions of 640x350, or 80x25 text with 16 colors, all at a refresh rate of 60 Hz. You will occasionally run into older systems that still use EGA; EGA-level graphics are the minimum requirement for Windows 3.x and so some very old systems still using Windows 3.0 may be EGA. There is of course no reason to stick with EGA when it is obsolete and VGA cards are so cheap and provide much more performance and software compatibility. Developed by IDM Interactive Training Division for

Skills Development Project

35

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting Video Graphics Adapter (VGA) The replacement for EGA was IBM's last widely-accepted standard: the Video Graphics Array or VGA. VGA, supersets of VGA, and extensions of VGA form today the basis of virtually every video card used in PCs. Introduced in the IBM PS/2 model line, VGA was eventually cloned and copied by many other manufacturers. When IBM fell from dominance in the market, VGA continued on and was eventually extended and adapted in many different ways. Most video cards today support resolutions and color modes far beyond what VGA really is, but they also support the original VGA modes, for compatibility. Most call themselves "VGA compatible" for this reason. Many people don't realize just how limited true VGA really is; VGA is actually pretty much obsolete itself by today's standards, and 99% of people using any variant of Windows are using resolution that exceeds the VGA standards. True VGA supports 16 colors at 640x480 resolution, or 256 colors at 320x200 resolution (and not 256 colors at 640x480, even though many people think it does). VGA colors are chosen from a palette of 262,144 colors (not 16.7 million) because VGA uses 6 bits to specify each color, instead of the 8 that is the standard today. VGA (and VGA compatibility) is significant in one other way as well: they use output signals that are totally different than those used by older standards. Older displays sent digital signals to the monitor, while VGA (and later) send analog signals. This change was necessary to allow for more color precision. Older monitors that work with EGA and earlier cards use so-called "TTL" (transistor-transistor logic) signaling and will not work with VGA. Some monitors that were produced in the late 80s actually have a toggle switch to allow the selection of either digital or analog inputs.

Super VGA (SVGA) and Other Standards Beyond VGA VGA was the last well-defined and universally accepted standard for video. After IBM faded from leading the PC world many companies came into the market and created new cards with more resolution and color depths than standard VGA (but almost always, backwards compatible with VGA). Most video cards (and monitors for that matter) today advertise themselves as being Super VGA (SVGA). What does a card saying it is SVGA really mean? Unfortunately, it doesn't mean much of anything. SVGA refers collectively to any and all of a host of resolutions, color modes and poorly-accepted pseudo-standards that have been created to expand on the capabilities of VGA. Therefore, knowing that a card that supports "Super VGA" really tells you nothing at all. In the current world of multiple video standards you have to find out specifically what resolutions, color depths and refresh rates each card supports. You must also make sure that the monitor you are using supports the modes your video card produces; here too "Super VGA compatible" on the monitor doesn't help you. To make matters more confusing, another term is sometimes used: Ultra VGA or UVGA. Like SVGA, this term really means nothing also. :^) Some people like to refer to VGA as 640x480 resolution, SVGA as 800x600, and UVGA as 1024x768. This is overly simplistic however, and really is not something that you can rely upon.

Developed by IDM Interactive Training Division for

Skills Development Project

36

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting The proliferation of video chipsets and standards has created the reliance on software drivers that PC users have come to know so well. While Microsoft Windows, for example, has a generic VGA driver that will work with almost every video card out there, using the higher resolution capabilities of your video card requires a specific driver written to work with your card. (The VESA standards have changed this somewhat, but not entirely). IBM did create several new video standards after VGA that expanded on its capabilities. Compared to VGA, these have received very limited acceptance in the market, mainly because they were implemented on cards that used IBM's proprietary Micro Channel Architecture (which received no acceptance in the market). You may hear these acronyms bandied about from time to time: 8514/A: This standard was actually introduced at the same time as standard VGA, and provides both higher resolution/color modes and limited hardware acceleration capabilities as well. By modern standards 8514/A is still rather primitive: it supports 1024x768 graphics in 256 colors but only at 43.5 Hz (interlaced), or 640x480 at 60 Hz (non-interlaced). XGA: This acronym stands for Extended Graphics Array. XGA cards were used in later PS/2 models; they can do bus mastering on the MCA bus and use either 512 KB or 1 MB of VRAM. In the 1 MB configuration XGA supports 1,024x768 graphics in 256 colors, or 640x480 at high color (16 bits per pixel). XGA-2: This graphics mode improves on XGA by extending 1,024x768 support to high color, and also supporting higher refresh rates than XGA or 8514/A.

Keyboard

Developed by IDM Interactive Training Division for

Skills Development Project

37

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting The set of typewriter-like keys that enables you to enter data into a computer. Computer keyboards are similar to electric-typewriter keyboards but contain additional keys. The keys on computer keyboards are often classified as follows: • • •

alphanumeric keys -- letters and numbers punctuation keys -- comma, period, semicolon, and so on. special keys -- function keys, control keys, arrow keys, Caps Lock key, and so on.

The standard layout of letters, numbers, and punctuation is known as a QWERTY keyboard because the first six keys on the top row of letters spell QWERTY. The QWERTY keyboard was designed in the 1800s for mechanical typewriters and was actually designed to slow typists down to avoid jamming the keys. Another keyboard design, which has letters positioned for speed typing, is the Dvorak keyboard. There is no standard computer keyboard, although many manufacturers imitate the keyboards of PCs. There are actually three different PC keyboards: the original PC keyboard, with 84 keys; the AT keyboard, also with 84 keys; and the enhanced keyboard, with 101 keys. The three differ somewhat in the placement of function keys, the Control key, the Return key, and the Shift keys. In addition to these keys, IBM keyboards contain the following keys: Page Up, Page Down, Home, End, Insert, Pause, Num Lock, Scroll Lock, Break, Caps Lock, Print Screen. There are several different types of keyboards for the Apple Macintosh. All of them are called ADB keyboards because they connect to the Apple Desktop bus (ADB). The two main varieties of Macintosh keyboards are the standard keyboard and the extended keyboard, which has 15 additional special-function keys.

Mouse A device that controls the movement of the cursor or pointer on a display screen. A mouse is a small object you can roll along a hard, flat surface. Its name is derived from its shape, which looks a bit like a mouse, its connecting wire that one can imagine to be the mouse's tail, and the fact that one must make it scurry along a surface. As you move the mouse, the pointer on the display screen moves in the same direction. Mice contain at least one button and sometimes as many as three, which have different functions depending on what program is running. Some newer mice also include a scroll wheel for scrolling through long documents. Invented by Douglas Engelbart of Stanford Research Center in 1963, and pioneered by Xerox in the 1970s, the mouse is one of the great breakthroughs in computer ergonomics because it frees the user to a large extent from using the keyboard. In particular, the mouse is important for graphical user interfaces because you can simply point to options and objects and click a mouse button. Such applications are often called point-and-click programs. The mouse is also useful for graphics programs that allow you to draw pictures by using the mouse like a pen, pencil, or paintbrush.

Developed by IDM Interactive Training Division for

Skills Development Project

38

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting There are three basic types of mice: 1. mechanical: Has a rubber or metal ball on its underside that can roll in all directions. Mechanical sensors within the mouse detect the direction the ball is rolling and move the screen pointer accordingly. 2. optomechanical: Same as a mechanical mouse, but uses optical sensors to detect motion of the ball. 3. optical: Uses a laser to detect the mouse's movement. You must move the mouse along a special mat with a grid so that the optical mechanism has a frame of reference. Optical mice have no mechanical moving parts. They respond more quickly and precisely than mechanical and optomechanical mice, but they are also more expensive. Mice connect to PCs in one of several ways: 1. Serial mice connect directly to an RS-232C serial port or a PS/2 port. This is the simplest type of connection. 2. PS/2 mice connect to a PS/2 port. 3. USB mice. Cordless mice aren't physically connected at all. Instead they rely on infrared or radio waves to communicate with the computer. Cordless mice are more expensive than both serial and bus mice, but they do eliminate the cord, which can sometimes get in the way

Computer case Computer case, most people called it wrongly by naming it as CPU, is actually a ‘house’ of the computer hardware parts of a computer. Generally, computer casing comes in two design, either tower case or desktop case. For better expendabilities, I would suggest that the tower computer cases are more ideal, and it best fits the endusers requirement. The reason behind this is that it is easier to upgrade, to add new devices, and easier to disassemble too. But, the disadvantages are tower computer cases are ‘wastage’ of your computer table space, whether you place it on the table or underneath it. They are already more than enough for my usage, but one factor must be considered, is that a tower case, regardless of high case, medium case or mini case, must has enough hard disk drive bay (inside the casing) for installing more than two or more hard disk drive.

Developed by IDM Interactive Training Division for

Skills Development Project

39

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting

PC Power Supplies The power supply converts electricity received from a wall outlet(120V AC in the U.S.A.) into DC current amounts that are needed by the various components of the system. There are 2 different types of power supplies that correspond to 2 different types of motherboards, and hence, case designs. AT - This is an older design in which the connector to the system board uses 2 6pin(P8/P9) connections. It is important that the 2 connectors are plugged into the system board correctly and not switched. P8 should be plugged into P1 on the system board and P9 should be connected to P2. ATX - A newer specification that uses a single 20 pin connection to the system board. These connectors are keyed to make sure that the connector is plugged in properly. Both models provide 4 levels of DC voltage. ATX power supplies add an additional voltage of +3.3V. The wires coming out of the power supply are color coded with the black one as the ground wire. • • • • • •

Yellow: +12 Blue: -12 Red: +5 White: -5 Circuitry: +/- 5 volts Motor: +/- 12 volts

Laptops and portables utilize an external power supply and rechargeable battery system. Batteries were typically nickel-cadmium, but newer technologies have introduced nickel metal-hydride and lithium-ion batteries that provide extended life and shorter recharge times. Lithium batteries are also used to power a computer's CMOS ROM. Installation/Removal To remove a power supply from a PC, follow these steps: 1. Unplug the computer from the wall 2. Disconnect all of the internal power connections(i.e. CD Rom, Motherboard, hard disk, etc) 3. Remove the 4 retaining screws 4. Pull power supply out of the computer

Motherboard The main circuit board of a microcomputer. The motherboard contains the connectors for attaching additional boards. Typically, the motherboard contains the CPU, BIOS, memory, mass storage interfaces, serial and parallel ports, expansion slots, and all the controllers required to control standard peripheral devices, such as the display screen, keyboard, and disk drive. Collectively, all these chips that reside on the motherboard are known as the motherboard's chipset.

Developed by IDM Interactive Training Division for

Skills Development Project

40

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting On most PCs, it is possible to add memory chips directly to the motherboard. You may also be able to upgrade to a faster PC by replacing the CPU chip. To add additional core features, you may need to replace the motherboard entirely.

Sound Card An expansion board that enables a computer to manipulate and output sounds. Sound cards are necessary for nearly all CD-ROMs and have become commonplace on modern personal computers. Sound cards enable the computer to output sound through speakers connected to the board, to record sound input from a microphone connected to the computer, and manipulate sound stored on a disk. Nearly all sound cards support MIDI, a standard for representing music electronically. In addition, most sound cards are Sound Blaster-compatible, which means that they can process commands written for a Sound Blaster card, the de facto standard for PC sound. Sound cards use two basic methods to translate digital data into analog sounds: •

FM Synthesis mimics different musical instruments according to built-in formulas.

•

Wavetable Synthesis relies on recordings of actual instruments to produce sound. Wavetable synthesis produces more accurate sound, but is also more expensive.

Video adapter A board that plugs into a personal computer to give it display capabilities. The display capabilities of a computer, however, depend on both the logical circuitry (provided in the video adapter) and the display monitor. A monochrome monitor, for example, cannot display colors no matter how powerful the video adapter. Many different types of video adapters are available for PCs. Most conform to one of the video standards defined by IBM or VESA. Each adapter offers several different video modes. The two basic categories of video modes are text and graphics. In text mode, a monitor can display only ASCII characters. In graphics mode, a monitor can display any bit-mapped image. Within the text and graphics modes, some monitors also offer a choice of resolutions. At lower resolutions a monitor can display more colors. Modern video adapters contain memory, so that the computer's RAM is not used for storing displays. In addition, most adapters have their own graphics coprocessor for performing graphics calculations. These adapters are often called graphics accelerators.

Developed by IDM Interactive Training Division for

Skills Development Project

41

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting Hard Disk Drives The hard disk drive in your system is the "data center" of the PC. It is here that all of your programs and data are stored between the occasions that you use the computer. Your hard disk (or disks) are the most important of the various types of permanent storage used in PCs (the others being floppy disks and other storage media such as CD-ROMs, tapes, removable drives, etc.) The hard disk differs from the others primarily in three ways: size (usually larger), speed (usually faster) and permanence (usually fixed in the PC and not removable). Hard disk drives are almost as amazing as microprocessors in terms of the technology they use and how much progress they have made in terms of capacity, speed, and price in the last 20 years. The first PC hard disks had a capacity of 10 megabytes and a cost of over $100 per MB. Modern hard disks have capacities approaching 100 gigabytes and a cost of less than 1 cent per MB! This represents an improvement of 1,000,000% in just under 20 years, or around 67% cumulative improvement per year. At the same time, the speed of the hard disk and its interfaces have increased dramatically as well. Your hard disk plays a significant role in the following important aspects of your computer system: •

• •

•

Performance: The hard disk plays a very important role in overall system performance, probably more than most people recognize (though that is changing now as hard drives get more of the attention they deserve). The speed at which the PC boots up and programs load is directly related to hard disk speed. The hard disk's performance is also critical when multitasking is being used or when processing large amounts of data such as graphics work, editing sound and video, or working with databases. Storage Capacity: This is kind of obvious, but a bigger hard disk lets you store more programs and data. Software Support: Newer software needs more space and faster hard disks to load it efficiently. It's easy to remember when 1 GB was a lot of disk space; heck, it's even easy to remember when 100 MB was a lot of disk space! Now a PC with even 1 GB is considered by many to be "crippled", since it can barely hold modern (inflated) operating system files and a complement of standard business software. Reliability: One way to assess the importance of an item of hardware is to consider how much grief is caused if it fails. By this standard, the hard disk is the most important component by a long shot. As I often say, hardware can be replaced, but data cannot. A good quality hard disk, combined with smart maintenance and backup habits, can help ensure that the nightmare of data loss doesn't become part of your life.

This chapter takes a very detailed look at hard disks and how they work. This includes a full dissection of the internal components in the drive, a look at how data is formatted and stored, a discussion of performance issues, and a full analysis of the two main interfaces used to connect hard disks to the rest of the PC. A discussion is also included about the many confusing issues regarding hard disks and BIOS versions, and support for the newer and larger hard disks currently on the market. Finally, a full description is given of logical hard disk structures and the functioning of the FAT and NTFS file systems, by far the most popular currently used by PCs. Developed by IDM Interactive Training Division for

Skills Development Project

42

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting Hard Disk Tracks, Cylinders and Sectors All information stored on a hard disk is recorded in tracks, which are concentric circles placed on the surface of each platter, much like the annual rings of a tree. The tracks are numbered, starting from zero, starting at the outside of the platter and increasing as you go in. A modern hard disk has tens of thousands of tracks on each platter. Data is accessed by moving the heads from the inner to the outer part of the disk, driven by the head actuator. This organization of data allows for easy access to any part of the disk, which is why disks are called random access storage devices. Each track can hold many thousands of bytes of data. It would be wasteful to make a track the smallest unit of storage on the disk, since this would mean small files wasted a large amount of space. Therefore, each track is broken into smaller units called sectors. Each sector holds 512 bytes of user data, plus as many as a few dozen additional bytes used for internal drive control and for error detection and correction.

Primary and Secondary Memory Primary Memory The main memory stores the program instructions and the data in binary machine code. The Control Unit deals with the instructions and the arithmetic and logic unit handles calculations and comparisons with the data. Data and instructions are moved by buses. There are two types of memory in the Immediate Access Store of the computer, RAM and ROM: RAM is Random Access Memory which loses its contents when the computer is switched off (it is volatile). This memory can be written to, instructions and data can be loaded into it. ROM, or Read Only Memory is non-volatile and is used to store programs permanently (the start-up or "boot" instructions, for example), the computer cannot store anything in this type of memory. When the programs and data files (known as the software) are not in RAM, they are stored on backing store such as tapes or discs. The tape or disc drives and any input and output devices connected to the CPU are known collectively as peripherals.

Developed by IDM Interactive Training Division for

Skills Development Project

43

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting Floppy disk

A soft magnetic disk. It is called floppy because it flops if you wave it (at least, the 5¼-inch variety does). Unlike most hard disks, floppy disks (often called floppies or diskettes) are portable, because you can remove them from a disk drive. Disk drives for floppy disks are called floppy drives. Floppy disks are slower to access than hard disks and have less storage capacity, but they are much less expensive. And most importantly, they are portable. Floppies come in three basic sizes: •

8-inch: The first floppy disk design, invented by IBM in the late 1960s and used in the early 1970s as first a read-only format and then as a read-write format. The typical desktop/laptop computer does not use the 8-inch floppy disk.

•

5¼-inch: The common size for PCs made before 1987 and the predecessor to the 8-inch floppy disk. This type of floppy is generally capable of storing between 100K and 1.2MB (megabytes) of data. The most common sizes are 360K and 1.2MB

•

3½-inch: Floppy is something of a misnomer for these disks, as they are encased in a rigid envelope. Despite their small size, microfloppies have a larger storage capacity than their cousins -- from 400K to 1.4MB of data. The most common sizes for PCs are 720K (doubledensity) and 1.44MB (high-density). Macintoshes support disks of 400K, 800K, and 1.2MB

Floppy drives While floppy drives still have a useful role in the modern PC, there is no denying their reduced importance. Very little attention is paid to floppy "performance" any more, and even choosing makes or models involves a small fraction of the amount of care and attention required for selecting other components. In essence, the floppy drive today is a commodity item! For this reason, I examine the floppy drive in this chapter but do not go into a great level of detail. In addition, since many aspects of floppy disk construction and logical operation are similar to those of hard disks, and since I did describe hard disks in a great level of detail, I make frequent references back to relevant sections in the chapter on hard disks Developed by IDM Interactive Training Division for

Skills Development Project

44

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting CD-ROM A type of optical disk capable of storing large amounts of data -- up to 1GB, although the most common size is 650MB (megabytes). A single CD-ROM has the storage capacity of 700 floppy disks, enough memory to store about 300,000 text pages. CD-ROMs are stamped by the vendor, and once stamped, they cannot be erased and filled with new data. To read a CD, you need a CD-ROM player. All CD-ROMs conform to a standard size and format, so you can load any type of CD-ROM into any CD-ROM player. In addition, CD-ROM players are capable of playing audio CDs, which share the same technology. CD-ROMs are particularly well-suited to information that requires large storage capacity. This includes large software applications that support color, graphics, sound, and especially video.

CPU Abbreviation of central processing unit, and pronounced as separate letters. The CPU is the brains of the computer. Sometimes referred to simply as the processor or central processor, the CPU is where most calculations take place. In terms of computing power, the CPU is the most important element of a computer system. On large machines, CPUs require one or more printed circuit boards. On personal computers and small workstations, the CPU is housed in a single chip called a microprocessor. Two typical components of a CPU are: • •

The arithmetic logic unit (ALU), which performs arithmetic and logical operations. The control unit, which extracts instructions from memory and decodes and executes them, calling on the ALU when necessary

Developed by IDM Interactive Training Division for

Skills Development Project

45

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting

Printers A device that prints text or illustrations on paper. There are many different types of printers. In terms of the technology utilized, printers fall into the following categories: •

daisy-wheel: Similar to a ball-head typewriter, this type of printer has a plastic or metal wheel on which the shape of each character stands out in relief. A hammer presses the wheel against a ribbon, which in turn makes an ink stain in the shape of the character on the paper. Daisy-wheel printers produce letter-quality print but cannot print graphics.

•

dot-matrix: Creates characters by striking pins against an ink ribbon. Each pin makes a dot, and combinations of dots form characters and illustrations. ink-jet: Sprays ink at a sheet of paper. Ink-jet printers produce high-quality text and graphics. laser: Uses the same technology as copy machines. Laser printers produce very high quality text and graphics. LCD & LED : Similar to a laser printer, but uses liquid crystals or light-emitting diodes rather than a laser to produce an image on the drum. line printer: Contains a chain of characters or pins that print an entire line at one time. Line printers are very fast, but produce low-quality print. thermal printer: An inexpensive printer that works by pushing heated pins against heat-sensitive paper. Thermal printers are widely used in calculators and fax machines.

• • • • •

Printers are also classified by the following characteristics: •

•

•

• •

quality of type: The output produced by printers is said to be either letter quality (as good as a typewriter), near letter quality, or draft quality. Only daisy-wheel, ink-jet, and laser printers produce letter-quality type. Some dot-matrix printers claim letter-quality print, but if you look closely, you can see the difference. speed: Measured in characters per second (cps) or pages per minute (ppm), the speed of printers varies widely. Daisy-wheel printers tend to be the slowest, printing about 30 cps. Line printers are fastest (up to 3,000 lines per minute). Dotmatrix printers can print up to 500 cps, and laser printers range from about 4 to 20 text pages per minute.

impact or non-impact: Impact printers include all printers that work by striking an ink ribbon. Daisy-wheel, dot-matrix, and line printers are impact printers. Nonimpact printers include laser printers and ink-jet printers. The important difference between impact and non-impact printers is that impact printers are much noisier. graphics: Some printers (daisy-wheel and line printers) can print only text. Other printers can print both text and graphics. fonts : Some printers, notably dot-matrix printers, are limited to one or a few fonts. In contrast, laser and ink-jet printers are capable of printing an almost unlimited variety of fonts. Daisy-wheel printers can also print different fonts, but you need to change the daisy wheel, making it difficult to mix fonts in the same document.

Developed by IDM Interactive Training Division for

Skills Development Project

46

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting

Bus Designs A computer bus is a method of transmitting data from one part of the computer to another part of the computer. Generally the computer bus will connect all devices to the computer CPU and main memory. The computer bus consists of two parts the address bus and a data bus. The data bus transfers actual data whereas the address bus transfers information about where the data should go. Found on this page you will be able to read about the various types of computer buses found on computers in the past and in the future.

ISA Introduced by IBM, ISA or Industry Standard Architecture was originally an 8-bit bus and later expanded to a 16-bit bus in 1984. When this bus was originally released it was a proprietary bus, which allowed only IBM to create peripherals and the actual interface. Later however in the early 1980's the bus was being created by other clone manufacturers. In 1993, Intel and Microsoft introduced a PnP ISA bus that allowed the computer to automatically detect and setup computer ISA peripherals such as a modem or sound card. Using the PnP technology an end-user would have the capability of connecting a device and not having to configure the device using jumpers or dipswitches. To determine if an ISA card is an 8-bit or 16-bit card physically look at the card. You will notice that the first portion of the slot closest to the back of the card is used if the card is an 8-bit card. However, if both sections of the card are being utilized the card is a 16-bit card. Today many manufacturers are trying to eliminate the usage of the ISA slot however for backwards compatibility you may find 1 or 2 ISA slots with additional PCI slots, AGP slots, etc. However, you may also not have any ISA slots. We highly recommend when purchasing any new internal expansion card that you stay away from ISA as it has for the most part disappeared.

MCA Short for Micro Channel Architecture, MCA was introduced by IBM in 1987, MCA or the Micro Channel bus was a competition for ISA BUS. The MCA bus offered several additional features over the ISA such as a 32-bit bus, automatically configure cards (similar to what Plug and Play is today), and bus mastering for greater efficiency. One of the major downfalls of the MCA bus was it being a proprietary BUS and because of competing BUS designs the MCA BUS never became widely used and has since been phased out of the desktop computers.

Developed by IDM Interactive Training Division for

Skills Development Project

47

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting EISA Short for Extended Industry Standard Architecture, EISA was announced September of 1988. EISA is a computer bus designed by 9 competitors to compete with IBM's MCA BUS. These competitors were AST Research, Compaq, Epson, Hewlett Packard, NEC, Olivetti, Tandy, WYSE, and Zenith Data Systems. The EISA Bus provided 32-bit slots at an 8.33 MHz cycle rate for the use with 386DX, or higher processors. In addition the EISA can accommodate a 16-bit ISA card in the first row. Unfortunately, while the EISA bus is backwards compatible and is not a proprietary bus the EISA bus never became widely used and is no longer found in computers today.

VLB The VESA (Video Electronics Standards Association) a nonprofit organization founded by NEC, released the VLB or VESA Local Bus 1.0 in 1992. The VLB is a 32bit bus that and had direct access to the system memory at the speed of the processor, commonly the 486 CPU (33 / 40 MHz). VLB 2.0 was later released in 1994 and had a 64-bit bus and a bus speed of 50 MHz. Unfortunately, because the VLB heavily relied on the 486 processor when the Pentium Processor arose in the Market place manufacturers began switching to PCI.

PCI Introduced by Intel in 1992, revised in 1993 to version 2.0, and later revised in 1995 to PCI 2.1. PCI is short for Peripheral Component Interconnect and is a 32-bit computer bus that is also available as a 64-bit bus today. The PCI bus is the most found and commonly used bus on computers today for computer expansion cards.

AGP Introduced by Intel in 1997, AGP or Advanced Graphic Port is a 32-bit bus designed for the high demands of 3-D graphics. AGP has a direct line to the computers memory which allows 3-D elements to be stored in the system memory instead of the video memory. For AGP to work in a computer must have the AGP slot which comes with most Pentium II and Pentium III machines. The computer also needs to be running Windows 95 OSR2.1, Windows 98, Windows 98 SE, Windows 2000, Windows ME or higher.

Developed by IDM Interactive Training Division for

Skills Development Project

48

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting USB USB or Universal Serial Bus is an external bus that supports transfer rates of 12 Mbps, can support 127 devices and supports hot plugging. Additional information on USB can be found on our USB page.

MINI PCI Mini PCI is a new standard which measures at 2.75-inch x 1.81-inch x 0.22-inch is a new standard developed by leading notebook manufactures. This technology could allow manufactures to lower their price as the motherboards would be simpler to design. Type I - Identical to Type II, except requires extra cables for connectors like the RJ11 and RJ-45. However, offers more flexibility to where it can be placed in the computer. Type II - Used when size is not important. Type II is able to integrate the RJ-11 and RJ-45 connectors and due away with extra cables. Type III - SO-DIMM style connector that can be installed with a mere 5 mm overall height above the system board. In addition cabling to the I/O connectors allow Type III cards to be placed anywhere in the system.

PCI-X PCI-X is a high performance bus that is designed to meet the increased I/O demands of technologies such as Fibre Channel, Gigabit Ethernet and Ultra3 SCSI. PCI-X capabilities include: Up to 133 MHz bus speed 64-Bit bandwidth 1GB/sec throughput More efficient bus operation for easier interface. Split Transactions allows an indicator device to make only one data request and relinquish the bus. Instead of constantly needing to poll the bus for a response. Byte Count that enables indicator to specify in advance the specific number of bytes requested, eliminating the inefficiency of speculative prefetches. Backwards compatibility

AMR Released September 8, 1998, AMR is short for Audio/Modem Riser. AMR allows an OEM to create one card that has the functionality of either Modem or Audio or both Audio and Modem on one card. This new specification allows for the motherboard to be manufactured at a lower cost and free up industry standard expansion slots in the system for other additional plug-in peripherals.

CNR Introduced by Intel February 7, 2000, CNR is short for Communication and Network Riser and is a specification that supports audio, modem USB and Local Area Networking interfaces of core logic chipsets. Developed by IDM Interactive Training Division for

Skills Development Project

49

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting

SKILLS DEVELOPMENT PROJECT Ministry of Tertiary Education & Training

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting Practice Labs 211

Developed by Interactive Training Division IDM Computer Studies (Pvt) Ltd. http://www.idm.edu

Developed by IDM Interactive Training Division for

Skills Development Project

50

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting

PRACTICE LAB1 OS Processes and Process Management An OS (i.e. operating system) manages resources for use by several programs and provides an abstract view on resources. The notion of a file for I/O operations is one important example, as is the notion of a process for execution of programs. An overview of the latter is given below. A simple computer contains a single processor which may be used to perform computations. An OS may merge different computations so that users may consider computations to be performed concurrently. In fact the use of the processor is granted for use by the various computations one by one, but so fast those users do not perceive the switching, much like a movie picture in fact is composed by a sequence of still pictures. The notion of a process is the abstraction that matches a user's belief to have the processor exclusively. To an OS a process is some data that can be manipulated. Since the OS also has to use the processor, this view is the OS's when no other process is executing. One important aspect of a process is its state in an OS's representation. 1. Explain what is a process? 2. Explain process management using necessary diagrams.

Developed by IDM Interactive Training Division for

Skills Development Project

51

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting

Memory Management When a user executes a program, the operating system creates an address space for it to run in. This address space will include the instructions for the program itself, as well as any data it requires. In a system with memory protection, each process is restricted by the operating system to accessing only the memory in its own address space. However, the combined program memory requirements often exceed the system's amount of physical memory (RAM) installed on a computer. So, modern operating system’s use a portion of the hard disk called a swap file to extend the amount of available memory. This technique, called virtual memory, treats physical memory as a cache of the most recently used data. In a virtual memory system, memory is divided into units called pages (a page is typically 4-8Kb in size). The set of addresses that identify locations in virtual memory is called the virtual address space. Each process is allocated a virtual address space. The virtual address space can range from 0-4GB on a 32-bit architecture. A process's address space contains the set of instructions and data that is mapped into virtual memory when a program is executed. Virtual memory addresses are translated into physical memory addresses through the use of a look-up table, called a page table. In addition to mapping the entire process into virtual memory, a subset of pages is also mapped into physical memory. As each instruction in the process executes, it is either found in physical memory or is not found (called a page fault). When a page fault occurs, the page that is needed must be moved from the hard disk into physical memory before the instruction can be executed. To make room for the new page, the operating system may need to decide which page to move out of physical memory. This is called swapping. A page fault is time-consuming because retrieving data from the hard disk is orders of magnitude slower than obtaining it directly from the physical memory. Operating systems attempt to minimize the number of page faults by swapping multiple pages at once. This becomes a trade-off between operating system overhead and the time saved by minimizing page faults, which is affected by the size of each process's working set. The operating system takes care of swapping and translating from virtual address space to physical address space. This means that the developer has a flat address space at his disposal. With a virtual memory scheme, the amount of memory available to a developer is seemingly limited only by the amount of hard drive space. In essence, virtual memory has much more memory available than physical memory alone because it removes the restriction that an entire process must be loaded into memory at one time. •

How does an operating system manage memory?

•

What is virtual memory?

•

How do you set the swap space for my operating system? 1. On UNIX 2. On Linux 3. In Windows(9x,NT,2000,XP)

Developed by IDM Interactive Training Division for

Skills Development Project

52

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting

File System and File System Recovery The hard disk is, of course, a medium for storing information. Hard disks grow in size every year, and as they get larger, using them in an efficient way becomes more difficult. The file system is the general name given to the logical structures and software routines used to control access to the storage on a hard disk system. Operating systems use different ways of organizing and controlling access to data on the hard disk, and this choice is basically independent of the specific hardware being used--the same hard disk can be arranged in many different ways, and even multiple ways in different areas of the same disk. The information in this section in fact straddles the fine line between hardware and software, a line which gets more and more blurry every year. The operating system is the large, relatively complex, low-level piece of software that interfaces your hardware to the software applications you want to run. The operating system you use is closely related to the file system that manages your hard disk data. The reason is a simple one: different operating systems use different file systems. Some are designed specifically to work with more than one, for compatibility reasons; others work only with their own file system. 1. What is a File system? 2. List and explain the file system or systems that can be used for • MS DOS • MS Windows 3.x • MS Windows 9x • MS Windows NT • MS windows 2000/XP • Unix • Linux • OS/2 3. What is the different between NTFS and FAT-16 FAT-32? 4. What is the minimum and the maximum partition size of each file system? 5. List the features of NTFS. 6. What are the advantages and disadvantages in each File System? 7. How you convert FAT to NTFS? Hard drives can fail for many reasons and you may be a candidate for hard drive recovery if you hear clicking, clunking, whirring, or ticking noises coming from your drive and or absolutely no noise at all. Drives often have read/write head failures causing that sound and if you hear it shut your system down right away and contact us for more information. In the interim, do not attempt to restart or power up the drive again as the read/write heads may touch the sensitive platters (where the data is stored) inside the drive and cause irreparable damage. You may also have a failed or failing hard drive if you get a blue screen, see error codes of "No Operating System Found", "Hard drive not found", "Head select error", "Drive read failure", "Drive write failure", "Bad track error", "Bad sector error" are some of the most common but there are many others. • •

List the utilities that you can recover the data in this kind of situations. What are the fault tolerance methods con be used to protect your data?

Developed by IDM Interactive Training Division for

Skills Development Project

53

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting

PRACTICE LAB 2 Software Installation and Preventive Maintenance Pre-installation Planning Make sure you meet the minimum system requirements. This sounds like a no-brainer, but it happens all the time. Sure, you can squeak Windows 2000 on a system that has less than the minimum hardware requirements, but you won't be happy with the performance. You'll want at least a Pentium 133 with 64Mb of RAM and 1GB of free disk space for Windows 2000 Professional. For Windows 2000 Server and Advanced Server you'll want 256Mb of RAM. Remember: Windows 2000 was built for tomorrow's hardware, not todays. If you can afford it, you'll be much happier if you upgrade to a new workstation or server with a 500 MHz processor and the entire RAM you can afford.

Document your Hardware and see if an updated Windows 2000 driver exists. If you don't already know every inch of your workstation or server, it's much easier to figure out your exact hardware configuration when Windows NT/95/98 is still installed. Do this first, and download the new Windows 2000 drivers before you start your installation. At the very least, download your SCSI, Video, Network Interface Card, and Modem drivers so you'll be able to get the rest later. Check the Hardware Compatibility List Many people skip this step and just proceed anyway, but you could be making a big mistake. Windows NT and Windows 2000 are a lot less flexible when it comes to hardware than Windows 95/98. The HCL exists for a reason. Check it first. Uninstall Anti-Virus software and Third party Utilities Anti-Virus programs and Disk/System Utilities (like Norton) can cause a number of issues during the upgrade process. Don't assume that utilities built for Windows 95/98 and older versions of Windows NT will work with Windows 2000. Uninstall them, check with the vendor, and be careful when your reinstall. If you must upgrade, backup your data first. I know it sounds like common sense, but I've heard lots of stories from people who have tried to upgrade their Operating Systems without a backup. Sad but true.

Developed by IDM Interactive Training Division for

Skills Development Project

54

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting Choose your File System When upgrading your Operating System, you have a few choices to make and some pre-configuration to do. First off, try to choose which file system you'll want installed. Microsoft recommends NTFS over FAT or FAT32, but that's up to you. If you choose FAT or FAT32 initially, you can upgrade to NTFS after the installation using NT's CONVERT utility. But you can't go back. Disable Disk Mirroring. If you’re running NT Server, disable any mirroring during the installation. You can reenable it after the installation is complete. Disconnect Uninterruptible Power Supplies. Windows 2000 features plug and play which will attempt to discover the function of any hardware connected to the system. If your UPS connects to your Workstation or Server using a serial cable, disconnect it before starting your installation. Give Windows 2000 its own separate partition Experienced NT Admins swear by this. Give Windows 2000 its own partition of at least 2 GB, or 4GB if you can afford it. If you install Windows 2000 on C:\, then install your applications on D:\ with data and other file storage on subsequent drives. This will simplify some backup strategies, give the registry and system files some breathing room, and leaves room for Service Packs and updates. It also leaves room for larger crash dump files, since your dump file will equal your physical memory + 1Mb.

Developed by IDM Interactive Training Division for

Skills Development Project

55

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting Preventive Maintenance Much as the name implies, preventive maintenance, often abbreviated PM, refers to performing proactive maintenance in order to prevent system problems. This is contrasted to diagnostic or corrective maintenance, which is performed to correct an already-existing problem. Anyone who has ever owned or cared for a car knows all about what preventive maintenance is. After all, you don't change your oil and air filter in response to a problem situation (normally), you do it so that your engine will last and you won't have car troubles down the road (no pun intended :^)). This chapter discusses some of the general concepts regarding preventive maintenance, the different types that are relevant to PCs, and how to set up a preventive maintenance schedule. The schedule can be considered a summary of preventive maintenance activities. Some types of preventive maintenance need to be performed more often than others. The frequency of preventive maintenance depends on the nature of the activity; some things just need to be addressed more often than others. It also depends a lot on what your PC is being used for. The interval for preventive maintenance on PCs can be determined based on elapsed time or on usage metrics. This is similar to how your car's oil and filter should be changed "every 3 months or 3,000 miles, whichever comes first". PC maintenance activities are usually specified as time-based, because this is easier (a PC has no odometer) but they should be performed more frequently depending on prevailing conditions. A PC used on the manufacturing floor of a steel mill needs to be cleaned more often than one being used in a hospital. A disk that is doing heavy Internet file transfers needs virus checking much more often than one that is used standalone and has no modem or floppy disk. One enemy of preventive maintenance is simply remembering to do. It's one thing to say "I will clean the read/write heads on my floppy disk every six months", and even to mean it. But how will you remember when the six months are up? One way to address this problem is through the use of a preventive maintenance schedule, which will remind you of when do perform key maintenance activities on your PC.

Checking all hard disks for read errors. Log in to your windows 9x Machine. Go to Startà Program Files à Ms DOS Type the command Scandisk

Checking the file system for errors Log in to your windows 9x, NT, 2000, XP Machine. Go to Startà Run àCmdà Type the command chkdsk à Press Enter. Developed by IDM Interactive Training Division for

Skills Development Project

56

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting

Defragmentation of all hard disk volumes To analyze the disk Log in to your windows 9x, NT, 2000, XP Machine. Go to Startà Run àCmdà Type the command defrag [Drive Letter] –a

To analyze and defragment. Log in to your windows 9x, NT, 2000, XP Machine. Go to Startà Run àCmdà Type the command defrag [Drive Letter] –f Cleaning the Disk. Log in to your windows 9 xs, NT, 2000, XP Machine

Click on the Start button;à choose Programs,à then Accessories,à then System Tools,à then Disk Cleanup. You will be presented with a screen that shows you exactly which files are no longer needed and exactly how much room they are taking up on your hard disk. Click on what you want to delete, and Windows will remove those items when you click on OK. Removing Old Programs You can use the Add/Remove Programs option in the Control Panel to remove the program. If the program you want to delete is not listed on the Add/Remove Program screen, you will have to remove it manually. When you install a program, often files are scattered in many different areas. Therefore the best way to remove a program is to purchase an uninstall program such as Cleansweep by Quarterdeck. When you purchase an uninstaller, make sure that you buy the version that is specifically written for your operating system. When uninstalling programs, it is always smart to first back up your hard disk. Also, remove one program at a time. Remove a program, make sure that everything is still working properly, then go back and delete the next program. No matter which operating system you use, you must occasionally go through the documents that you have created, like letters, spreadsheets, pictures, etc., to weed out unnecessary files. Delete any file you will not need in the future. If you are hesitant about deleting a file, you can copy it to a floppy disk, delete it from your hard disk, and keep the floppy as an archival copy. Developed by IDM Interactive Training Division for

Skills Development Project

57

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting Scanning all hard disks and files for viruses. According to Fred Cohen's well-known definition, a computer virus is a computer program that can infect other computer programs by modifying them in such a way as to include a (possibly evolved) copy of itself. Note that a program does not have to perform outright damage (such as deleting or corrupting files) in order to be called a "virus". However, Cohen uses the terms within his definition (e.g. "program" and "modify") a bit differently from the way most anti-virus researchers use them, and classifies as viruses some things which most of us would not consider viruses. Many people use the term loosely to cover any sort of program that tries to hide its (malicious) function and tries to spread onto as many computers as possible. (See the definition of "Trojan".) Be aware that what constitutes a "program" for a virus to infect may include a lot more than is at first obvious - don't assume too much about what a virus can or can't do! These software "pranks" are very serious; they are spreading faster than they are being stopped, and even the least harmful of viruses could be fatal. For example, a virus that stops your computer and displays a message, in the context of a hospital life-support computer, could be fatal. Even those who created the viruses could not stop them if they wanted to; it requires a concerted effort from computer users to be "virus-aware", rather than the ignorance and ambivalence that have allowed them to grow to such a problem. Install a Proper Virus Guard and Install the Latest updates.

Developed by IDM Interactive Training Division for

Skills Development Project

58

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting

PRACTICE LAB 3 Troubleshooting Tools Microsoft Diagnostics Software utility named msd.exe that was included with Microsoft Windows 3.x that listed computer system information. Below is a listing of information available through Microsoft diagnostics: • • • • • • • • • • • • •

Computer brand and processor information Memory (Total, EMS, and XMS) Video (Type such as VGA and manufacturer) Network Operating System versions Type of Mouse if installed Disk drives (and partitions) LPT ports COM ports IRQ status TSR programs Device drivers Other adapters

Download the MSD.EXE from ftp://ftp.microsoft.com/softlib/mslfiles/msdzip.exe Double Click on it and Press “Y” Check your systems above configurations.

How to Generate MSD Reports An MSD report is a diagnostics report that lets us know what system type you have and how it is setup. To run an MSD report, go to the C:\WINDOWS> prompt and type MSD. Once in the diagnostics:

1. 2. 3. 4. 5.

Press Alt F to access the file menu Press P for Print Report Press the space bar to place an X in the Report All column Press Enter to continue with the report Type in your information using the TAB key to move to the next line. DO NOT PRESS ENTER UNTIL YOU HAVE COMPLETED ALL INFORMATION. (If you do you will either need to rerun the report or include all customer information on a sheet with your report). 6. Press Enter once you complete customer information. 7. Press Alt F again and X to exit the MSD program .

Device Manager First introduced with the release of Microsoft Windows 95 the Windows device manager is a program that allows a user to view hardware devices and their status. Developed by IDM Interactive Training Division for

Skills Development Project

59

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting Device manager is available in Microsoft Windows 95, Windows 98, Windows ME, Windows 2000 and Windows XP. To start Device Manager: 1. Click Start, and then click Control Panel. 2. Click Performance and Maintenance, and then click System. 3. Click the Hardware tab, and then click Device Manager.

Troubleshooting Information If there is a problem with a device, it is listed in the hardware tree. Also, the problem device has a symbol that indicates the type of problem: A black exclamation point (!) on a yellow field indicates the device is in a problem state. Note that a device that is in a problem state can be functioning. A problem code explaining the problem is displayed for the device. A red "X" indicates a disabled device. A disabled device is a device that is physically present in the computer and is consuming resources, but does not have a protectedmode driver loaded. A blue "i" on a white field on a device resource in Computer properties indicates that the Use automatic settings feature is not selected for the device and that the resource was manually selected. Note that this does not indicate a problem or disabled state. A green question mark "?" in Device Manager means that a compatible driver for this device is installed, indicating the possibility that all of the functionality may not be available. Note that this applies only to Windows Millennium Edition (Me). NOTE: Some sound cards and video adapters do not report all of the resources that they use to Windows. This can cause Device Manager to show only one device in conflict, or no conflicts at all. This can be verified by disabling the sound card, or by using the standard VGA video driver to see if the conflict is resolved. Note that this is a known problem with S3 video adapters and 16-bit Sound Blaster sound cards, or those sound cards that are using Sound Blaster emulation for Sound Blaster compatibility. When you double click a specific device in Device Manager, you see a property sheet. The property sheet has a General tab. NOTE: Some devices may have other tabs besides the General tab. Not all property sheets have the same tabs; some devices may have a Resources tab, Driver tab, and Settings tab, or some combination of these.

Developed by IDM Interactive Training Division for

Skills Development Project

60

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting At the top of the property sheet, there is a description of the device. When you click the Resources tab, the window in the middle of the tab indicates which resource types are available for the selected device. The list box at the bottom contains a Conflicting device list. This list indicates a conflict with an error code. For example, to edit the Input/Output Range setting: 1. Click the Use automatic settings check box to clear it. 2. Click Change Setting. 3. Click the appropriate I/O range for the device. NOTE: To disable a device in Device Manager, right-click the device, and then click Disable.

Control Panel Applets The control panels in Windows contain many of the operating system's im portant settings. You should be familiar with what options can be located in each of the control panels and how to change them. The best way to learn is just to browse the control panels on your computer. Below is a list of the more important Windows control panels. Control panels are named slightly differently in every version of Windows, but the options are generally similar.

Add New Hardware Also called Add Hardware. This control panel is used for adding new hardware. Often, Windows will automatically detect new hardware and guide you through the installation process. If it does not, use this control panel to install the hardware.

Developed by IDM Interactive Training Division for

Skills Development Project

61

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting Let the Add New Hardware Wizard resolve your device problems If you are having problems with a particular device after installing Windows 98 or other software, try removing it and then let Windows 98 reinstall the device. Here's how to do it: 1. On the Start menu, point to Settings, point to Control Panel, and then double-click the System icon. 2. Click the Device Manager tab. (The problem category should automatically open and a symbol should indicate which device is faulty. If it's not working properly, there will be a yellow circle with a black exclamation point inside it; if it's not working at all, there will be a red X.

3. Click once on the problem item to highlight it, and then click Remove. 4. During start up, Windows 98 should detect as missing the device you just removed and automatically run the Add New Hardware Wizard. If you recently downloaded new drivers from any of your hardware manufacturers’ sites, or from Windows Update, be sure to use the wizard's Have Disk option to ensure that Windows 98 installs the new drivers and not any old ones. 5. Hint: When you download new drivers from hardware manufacturers or Windows Update, copy them to a floppy disk and label them. This way, if you ever need to re-install them, and don't have access to the Internet, they are right where you need them.

Add/Remove Programs This control panel is the appropriate place to uninstall programs that did not come with their own uninstaller. Simply deleting files or folders is not a good way to remove an unwanted program. This control panel also allows you to control which Windows Components are installed - you can free up resources by removing unnecessary components .

To add a program from a CD or floppy disk 1. Open Add/Remove Programs in Control Panel. 2. Click Add New Programs, and then click CD or Floppy. 3. Follow the instructions on your screen.

Developed by IDM Interactive Training Division for

Skills Development Project

62

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting Note •

To open a Control Panel item, click Start, point to Settings, click Control Panel, and then double-click the appropriate icon.

•

When using Add/Remove Programs, you can install only programs that were written for Windows operating systems.

•

When you open a program, or try to perform a task within a program, you may see a dialog box indicating that the program is being installed or updated by Windows Installer. This can occur if your administrator has set up the program to install this way, if program files have been deleted or corrupted, or if you are trying to use a program feature that was not installed during setup. If the program was installed from a CD-ROM, or if you are no longer connected to the network, Windows Installer may ask you for the CD-ROM. When Windows Installer finishes, the program or feature you are trying to use starts

To change or remove a program 1. Open Add/Remove Programs in Control Panel. 2. Click Change or Remove Programs, then click the program you want to change or remove. 3. Click the appropriate button: •

To change a program, click Change/Remove or Change.

•

To remove a program, click Change/Remove or Remove.

Caution •

When you click Change/Remove, some programs may be removed without prompting you further.

Note •

To open a Control Panel item, click Start, point to Settings, click Control Panel, and then double-click the appropriate icon.

•

When using Add/Remove Programs, you can remove only programs that were written for Windows operating systems. For other programs, check the documentation to see if other files (such as .ini files) should be removed.

•

When you open a program, or try to perform a task within a program, you may see a dialog box indicating that the program is being installed or updated by Windows Installer. This can occur if your administrator has set up the program to install this way, if program files have been deleted or corrupted, or if you are trying to use a program feature that was not installed during setup. If the program was installed from a CD-ROM, or if you are no longer connected to the network, Windows Installer may ask you for the CD-ROM. When Windows Installer finishes, the program or feature you are trying to use starts. Developed by IDM Interactive Training Division for

Skills Development Project

63

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting To add or remove a Windows 2000 component 1. Open Add/Remove Programs in Control Panel. 2. Click Add/Remove Windows Components. 3. Follow the instructions in the Windows Components wizard. Note •

You must be logged on as an administrator or a member of the Administrators group in order to complete this procedure. If your computer is connected to a network, network policy settings may also prevent you from completing this procedure.

•

To open a Control Panel item, click Start, point to Settings, click Control Panel, and then double-click the appropriate icon.

•

Certain Windows Components require configuration before they can be used. If you installed one or more of these components, but did not configure them, when you click Add/Remove Windows Components, a list of components that need to be configured is displayed. To configure a component, click Configure, and then follow the instructions on the screen. To add a new component, click Components, and follow the instructions in the Windows Components wizard.

Display This control panel allows you to control the appearance of your computer. You can change your background wallpaper and screen saver, select the display resolution and change the color scheme. 1. To access display settings click on Start>Settings>Control Panel. 2. Select "Display" and choose the Settings Tab. 3. Do not use 256 colors as your graphics setting. You should choose to use at least "high color". 4. Using 256 colors can result in colors not being displayed properly.

Modems Also called Phone and Modem Options. Here, you can configure your modem settings and dialing options (including configuring for long distance or calling card dialing).

Network Also called Network Connections. This control panel allows you to configure your network settings. Please see the section on Networking for Princeton-specific configuration information. Developed by IDM Interactive Training Division for

Skills Development Project

64

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting Configuring the Network Adapter Software 1. Open the Control Panel (click on Start --> Settings) and double-click on the Network icon. 2. You need to run Add/Remove Programs and Windows Setup, which are both available in the Control Panel window, to install network support. 3. Click on the Add button and double-click on Adapter. 4. Select your Ethernet adapter manufacturer and type from the list. If you wish to use a network adapter that is not listed, contact the manufacturer for a Windows compliant driver. 5. The Network Control Panel will display several protocols and clients, such as Client for Microsoft Networks, Client for NetWare Networks, IPX/SPXcompatible Protocol, and NetBEUI.

Installing the TCP/IP Protocol 1. Click on the Add button from the Network Control Panel again to add a new Protocol. 2. Select Manufacturer Microsoft and Network Protocol TCP/IP. 3. Click OK to close the Network Control Panel. 4. Unless you did a full installation of Windows, you will be prompted for the Windows installation disks. In some cases, the installation will require the Windows disks even if you did a full installation. Be sure to use the appropriate version of the Windows CD. New hard disks may come with the "B" version (OSR2) of Windows 95 or with Windows 98. Mixing versions can render the PC unbootable. 5. When the installation program finishes copying the files, restart your PC

Configuring TCP/IP Properties 1. Open the Control Panel (click on Start -> Settings) and double-click on the Network icon. 2. In the Network dialog box, click the Configuration tab if it isn't already selected. 3. In the list of network components installed, select the entry for the TCP/IP protocol and your network adapter Then, click the Properties button. 4. Click on the IP Address tab (if it isn't already selected) and verify that the default Obtain an IP address automatically is selected. 5. Click on the DNS Configuration tab and enter the following information: 1. Click on the Enable DNS option button. 2. In the Host field, enter the host name for your PC which you received during registration 3. In the Domain field, enter: dur.ac.uk (For this contact your network Administrator) 4. In the DNS Server Search Order field, enter the following IP addresses, clicking the Add button after entering each one: 203.115.0.19 and 203.115.0.1(For this contact your network Administrator) 5. In the Domain Suffix Search Order, enter: dur.ac.uk (For this contact your network Administrator) Developed by IDM Interactive Training Division for

Skills Development Project

65

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting

6. Click OK, and then click OK in the Network dialog box. 7. Click Yes when prompted to restart your PC.

Users Also called User Accounts. This control panel is used for creating and modifying local user accounts, setting and changing passwords.

1. Login as Administrator. 2. Select Start/Programs/Administrative Tools/Computer Management. 3. From the Computer Management snap-in open the System Tools/Local Users and Groups node. Right-click on the Users node and select New User…. The New User dialog box should appear. 4. Enter your username (first initial lastname, e.g. dglazer), full name and password/confirm password. 5. Uncheck the default selection of “User must change password at next logon”. 6. Press Create button. 7. Press Close to exit the window. The new user now appears in the right pane of the Computer Management snap-in.

Power Management Also called Power Options. In this control panel are the options for power saving features (which are especially important on a laptop). You can have your computer go into "sleep" or "hibernate" mode and shut off its monitor or hard drive, saving power when you are away from the computer. 1. Select Start > Settings > Control Panel from the Start Menu. 2. Double click the Display icon in the Control Panel window. 3. In the Display Properties dialog, click the Screen Saver tab, then click the Power button in the Energy saving features of monitor box. 4. Under Power Schemes, select Home/Office Desk. Note: Some of the options shown here, such as System Standby and System Hibernates, may not appear on your computer. If this is the case, simply skip the steps that do not apply to you. The options available may vary depending on your computer's capabilities. 5. Set Turn Off Monitor after 10 minutes. 6. Set Turn Off Hard Drives to Never. 7. Set System Standby to Never. 8. Set System Hibernates to Never. 9. Click OK.

Developed by IDM Interactive Training Division for

Skills Development Project

66

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting System This control panel contains the system's general information. It tells you the exact version of your operating system as well as how much RAM the system has. It also provides a Device Manager for viewing what hardware or virtual devices may be causing problems (the Device Manager also allows you to update hardware drivers). More advanced system configuration tools can be found in this control panel, though changing them is not recommended without a full understanding of their effects.

System Configuration Editor Configuration Editor allows you to examine and edit your system files (config.sys, win.ini, etc.) all in one place with a clean, orderly, tabbed document interface. Just click on the tab to go from one file to another. You already have System Configuration Editor (sysedit.exe), which comes with windows, but it uses the awkward multi-window approach. Compare the two and you'll see why Configuration Editor is easier to use. 1) 2) 3) 4)

Click the "Start" button. Select Run from the pop-up menu Type SYSEDIT in the white text box A new window will open which will have within it four other windows, each one containing a file. 5) You can simply click on the title of any of the windows and that will change the focus to that window and then by clicking anywhere within that window you can modify the contents. 6) If any changes were made, the computer will present you with a warning pop-up window asking if you want to save the changes. You click on the "Yes" button to continue. At that time the files will be saved and the sysedit program will close. 7) The changes will take effect the next time you reboot your computer. A similar method for making changes to the above files from within DOS is to use the EDIT function. This would be done by going to a DOS prompt and typing the command EDIT autoexec.bat <enter> A DOS based window would open allowing you to make changes. When you are done you would use a similar method of exiting by selecting File Exit from the top menu.

Developed by IDM Interactive Training Division for

Skills Development Project

67

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting

PC Tools List and experience third party tools for 1. Disk defragmenting 2. Disk Cleaning 3. Disk Partitioning. 4. Software and operating system deploying. 5. Operating system restoring. 6. Back up FDISK is often the tool of choice for ex-DOS users when managing drive partitions. This tool works great as long as you are working with all primary partitions or only FAT, FAT32, and OS/2's HPFS. FDISK is not even able to recognize NTFSformatted extended partitions. So, if you need to delete such a partition, you either need to have access to a Windows NT, Windows 2000, or Windows XP OS on the same system as the hard drive in question, and boot into the setup routines of one of these three OSes to use the text-based partition configuration tool, or use a third party tool. I've already mentioned Partition Magic, but there is another tool you may want to look at: DELPART. DELPART is a DOS based tool from Windows NT 3.51; you can find it floating around the Internet with a quick search on "delpart". This too can delete any and all partitions on a hard drive, thus making way for easy repartitioning and new OS installation. • •

Use FDISK to partition a Hard disk Use DELPART to partition a Hard disk

Norton Utilities Norton Utilities is a group of programs that let you do everything from deleting items so that they cannot be recovered to watching your system for problems. It will find and fix problems associated with hardware or software, help you recover files you accidentally erased, and monitor your system at all times. This series will explain to you how to accomplish all of these tasks and more. Experience the following Norton utilities. Install Norton utilities Set Up Your Options Step 1: Start Norton System Works Double-click the Norton System Works icon located on the desktop. You can also click the Start button, then Programs, then Norton SystemWorks, then Norton SystemWorks. Step 2: Click Options Click the Options button and then choose the Norton Utilities submenu. This will take you to the options screen for setting up the software. Step 3: Tabs There are six different tabs that you can set options for. The tabs are General Settings, Startup Programs, WipeInfo Settings, System Check Scheduler, Recycle Bin, and Norton Protection. Click the tab for the one that you want to change the options for. Developed by IDM Interactive Training Division for

Skills Development Project

68

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting Step 4: General and Startup The General tab lets you specify if you want to see introductions and splash screens before starting any of the programs. The Startup tab lets you decide which of the programs will be run on startup. Step 5: WipeInfo and Norton Protection The WipeInfo tab sets up what type of deletion you want when you delete a file. You can set it up to write over the information once or several times. The Norton Protection tab is used to set the number of days before files that were deleted under DOS will be protected. Step 6: Recycle Bin and Scheduler The Recycle Bin tab lets you decide what will open when you double-click the recycle bin and also what the recycle bin will look like on your desktop. The System Check Scheduler tab lets you set up when you certain events to be performed.

Conducting a Checkup Step 1: Start Norton SystemWorks Double-click the Norton SystemWorks icon located on the desktop. You can also click the Start button, then Programs, then Norton SystemWorks, then Norton SystemWorks. Step 2: Choose Find & Fix Submenu On the left side of the screen are the menu items. Click the Norton Utilities menu and then the Find and Fix Problems submenu. This will give you access to four different utilities. Step 3: Execute Norton System Check Click on the Norton System Check menu located on the right side of the window. This will start the program. Step 4: Start Diagnosing Put a checkmark into each of the categories that you want the software to check. When you've finished deciding which categories click the Next button and the software will start analyzing your system. Step 5: Fix Problems After the software has finished scanning the system, click the Finish button and a list of the problems that were found will be displayed. To repair the items, highlight the ones that you want to repair and click the Repair button. If you want to repair each item individually, double-click one of the items and you'll be asked if you want to repair each item or have the software do it automatically.

Developed by IDM Interactive Training Division for

Skills Development Project

69

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting Finding Windows Problems Step 1: Start Norton SystemWorks Double-click the Norton SystemWorks icon located on the desktop. You can also click the Start button, then Programs, then Norton SystemWorks, then Norton SystemWorks. Step 2: Choose Find & Fix Submenu On the left side of the screen are the menu items. Click the Norton Utilities menu and then the Find and Fix Problems submenu. This will give you access to four different utilities. Step 3: Execute Norton WinDoctor Click on the Norton WinDoctor menu located on the right side of the window. This will start the program. This program will check the windows registry file to ensure that all of the entries are correct. Step 4: Choose Tests to Run You can decide to run all of the tests which are the recommended option or you can choose to only run some of the tests. You make your choice. If you decide to choose the tests, remove the checkmark from the tests that you don't want to perform. Step 5: Fix Found Problems If any problems were found to exist during the testing they will be shown to you when you click the Finish button. To fix a problem, highlight the problem that you want to fix and click the Repair button. The software will automatically make the repairs for you.

Diagnose and Repair Step 1: Start Norton SystemWorks Double-click the Norton SystemWorks icon located on the desktop. You can also click the Start button, then Programs, then Norton SystemWorks, then Norton SystemWorks. Step 2: Choose Find & Fix Submenu On the left side of the screen are the menu items. Click the Norton Utilities menu and then the Find and Fix Problems submenu. This will give you access to four different utilities. Step 3: Execute Norton Disk Doctor Click on the Norton Disk Doctor menu located on the right side of the window. This will start the program. This program will test the integrity of the hard drive. Step 4: Set Options By clicking the Options button, you can set what will happen when the program runs. There are four tabs available. The most important one is the General tab. The other three tabs are for appearances, how many times the disk will be scanned, and tests that should be skipped. On the General tab, you need to decide about your repair options. Yo u can have the software automatically fix the problems, skip the problem, or prompt you for action to take.

Developed by IDM Interactive Training Division for

Skills Development Project

70

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting Step 5: Diagnose the Disk Click the Diagnose button and the process will begin. A list of what is being checked will be displayed and a checkmark will be put next to the category when the check has been completed. Step 6: Viewing Results After the completion of the scanning, a list of the results that were found will be displayed. If there are any problems, follow the instructions for fixing the problem.

Restoring Deleted Files Step 1: Start Norton SystemWorks Double-click the Norton SystemWorks icon located on the desktop. You can also click the Start button, then Programs, then Norton SystemWorks, then Norton SystemWorks. Step 2: Choose Find & Fix Submenu On the left side of the screen are the menu items. Click the Norton Utilities menu and then the Find and Fix Problems submenu. This will give you access to four different utilities. Step 3: Execute UnErase Wizard Click on the UnErase Wizard menu located on the right side of the window. This will start the program. This program will let you recover any files that have been deleted. It may even be able to recover files that have been deleted from the Recycle Bin. Step 4: Find Files When you first bring up the UnErase Wizard, you'll have to choose what types of files you want the software to look for. You can choose Recently deleted files, Protected files, and Files meeting your criteria. When you've decided this, click the Next button. Step 5: Choose a File Highlight the file that you want to recover. Once you've highlighted this file, click the Recover button. If you want to recover more files or try to find files that meet certain criteria click the Next button to continue with the process. Undoing Fixes Step 1: Start Norton SystemWorks Double-click the Norton SystemWorks icon located on the desktop. You can also click the Start button, then Programs, then Norton SystemWorks, then Norton SystemWorks. Step 2: Choose Find & Fix Submenu On the left side of the screen are the menu items. Click the Norton Utilities menu and then the Find and Fix Problems submenu. This will give you access to four different utilities. Step 3: Run a Program Norton System Check, Norton WinDoctor, and Norton Disk Doctor each have the ability to undo fixes that have been made. Execute the one that you want to undo the changes in. Developed by IDM Interactive Training Division for

Skills Development Project

71

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting Step 4: History Report When the first screen is displayed, click the Cancel button. You'll know be shown the problems screen. Click on the History icon and the history report will be displayed. This shows all of the problems that have been fixed in the past. Step 5: Undo the Fix Highlight the problem that you want to undo and click the Undo icon. You'll be asked if you're sure you want to undo the fix. If you do want to undo it, click the Yes button. If not, click the No button.

Speeding Up Your Computer Step 1: Start Norton SystemWorks Double-click the Norton SystemWorks icon located on the desktop. You can also click the Start button, then Programs, then Norton SystemWorks, then Norton SystemWorks. Step 2: Click Improve Performance On the left side of the screen are the menu items. Click the Norton Utilities menu and then the Improve Performance submenu. This will give you access to four different utilities. Step 3: Execute Speed Disk Click on the Speed Disk menu located on the right side of the window. This will start the program which will help defragment your hard drive and move the files around so that your computer will operate more efficiently. Step 4: Recommended Action After the program is started, the hard drive will be analyzed. The software will let you know what was found and will show you how fragmented the drive is and give you a recommendation as what should be done. Choose which option you want and click the Start button when you're ready to defragment your drive. Depending on the size of your hard drive and the amount of fragmentation, it may take a while for the entire process to complete.

Optimizing the Registry File Step 1: Start Norton SystemWorks Double-click the Norton SystemWorks icon located on the desktop. You can also click the Start button, then Programs, then Norton SystemWorks, then Norton SystemWorks. Step 2: Click Improve Performance On the left side of the screen are the menu items. Click the Norton Utilities menu and then the Improve Performance submenu. This will give you access to four different utilities. Step 3: Execute Optimization Wizard Click on the Norton Optimization Wizard menu located on the right side of the window. This will start the program. This program will look at the registry file and try to minimize its size and rearranging its structure so as to increase the access speed. Developed by IDM Interactive Training Division for

Skills Development Project

72

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting Step 4: Optimization Choices The wizard will walk you through the choices for optimizing the files. You can optimize two files, the swap file and the registry file. Click the Next button and choose if you want to optimize these files. Step 5: Optimize the System After you've chosen which of the two options to optimize you'll need click the Reboot button. After the files have been optimized, the system will automatically reboot itself to finish the process. Make sure that you've saved all of your files before clicking the Reboot button

Add Sensor to System Doctor Step 1: Start Norton SystemWorks Double-click the Norton SystemWorks icon located on the desktop. You can also click the Start button, then Programs, then Norton SystemWorks, then Norton SystemWorks. Step 2: Choose Preventive Maintenance On the left side of the screen are the menu items. Click the Norton Utilities menu and then the Preventive Maintenance submenu. This will give you access to four different utilities. Step 3: Execute Norton System Doctor Click on the Norton System Doctor menu located on the right side of the window. This will start the program. This program will continuously monitor your computer for problems and let you know before they happen. Step 4: Sensor List Click on the Sensors menu and choose the category that you want to add. There are six different categories that you can add from. When you move to a submenu, you'll have further choices to make. Choose the one that you want and it will be added to the Norton System Doctor window.

System Doctor Sensor Editing Step 1: Start Norton SystemWorks Double-click the Norton SystemWorks icon located on the desktop. You can also click the Start button, then Programs, then Norton SystemWorks, then Norton SystemWorks. Step 2: Choose Preventive Maintenance On the left side of the screen are the menu items. Click the Norton Utilities menu and then the Preventive Maintenance submenu. This will give you access to four different utilities. Step 3: Execute Norton System Doctor Click on the Norton System Doctor menu located on the right side of the window. This will start the program. This program will continuously monitor your computer for problems and let you know before they happen. Developed by IDM Interactive Training Division for

Skills Development Project

73

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting Step 4: Choose the Sensor Right-click the sensor that you want to change the properties for. You'll get a menu of selections. Choose the top menu item labeled Properties. and you'll get the properties box. You'll now be able to change the settings for that sensor. Step 5: Other Menu Items When you right-click a sensor there are several different menu items. Update the status of the sensor immediately. If you want to remove a sensor, click the Remove menu. To find out information about the sensor click the Sensor Information menu. Some of the sensors have programs associated with them. If this sensor is one, you can click the Open program name menu item.

Permanently Deleting Data Step 1: Start Norton SystemWorks Double-click the Norton SystemWorks icon located on the desktop. You can also click the Start button, then Programs, then Norton SystemWorks, then Norton SystemWorks. Step 2: Choose Preventive Maintenance On the left side of the screen are the menu items. Click the Norton Utilities menu and then the Preventive Maintenance submenu. This will give you access to four different utilities. Step 3: Execute Norton WipeInfo Click on the Norton WipeInfo menu located on the right side of the window. This will start the program. This program will delete files from your computer so that you can't recover them, even with undo. You can also clear the free space on your hard drive. Step 4: Choose the Type of Deletion You've got three choices as to what you want to wipe clean. You can choose either files, folders, or free space. When you make your choice click the Next button to continue with the process. Step 5: Select Files, Folders or Space Depending on the choice you made in the previous step, you'll need to choose which files or folders to delete. If you had chosen free space you need to decide which hard drives to clean. Step 6: Wipe Options Choose the type of wipe that you want to accomplish. The Fast Wipe will write over the space once. The Government Wipe will write over the space with digits the specified number of times. The more times that the space is written over, the harder it would be to recover the file.

Developed by IDM Interactive Training Division for

Skills Development Project

74

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting Imaging Your Drive Step 1: Start Norton SystemWorks Double-click the Norton SystemWorks icon located on the desktop. You can also click the Start button, then Programs, then Norton SystemWorks, then Norton SystemWorks. Step 2: Choose Preventive Maintenance On the left side of the screen are the menu items. Click the Norton Utilities menu and then the Preventive Maintenance submenu. This will give you access to four different utilities. Step 3: Execute Image Click on the Image menu located on the right side of the window. This will start the program. This program takes a picture of your hard drive and keeps that information. This information is used when trying to rebuild deleted files or if there is a problem with the structure of your folders. Step 4: Setting Options Click the Options button and you'll be taken to the options screen. Here you can set the software up to create an image every time that the computer starts. You also can tell it what drives to image. Step 5: Create an Image Choose which drives you want to image and click the Image button. The software will start creating the image and a progress bar will be displayed at the bottom of the window showing the status.

Diagnose Hardware Problems Step 1: Start Norton SystemWorks Double-click the Norton SystemWorks icon located on the desktop. You can also click the Start button, then Programs, then Norton SystemWorks, then Norton SystemWorks. Step 2: Choose Troubleshoot Submenu On the left side of the screen are the menu items. Click the Norton Utilities menu and then the Troubleshoot submenu. This will give you access to four different utilities. Step 3: Execute Norton Diagnostics Click on the Norton Diagnostics menu located on the right side of the window. This will start the program. This program will complete eleven different tests to analyze your hardware for possible problems. Step 4: Conducting the Tests On the left side of the window is a section that lists all of the tests that are available. If you want to conduct all of the tests, highlight Do All Tests and click the Test button. If you only want to conduct a test on a specific piece of hardware, highlight that hardware item and click the Test button. Step 5: View the Results During the course of the testing, you'll see the results displayed in the window. You can see what test was performed and if the component passed the test. Developed by IDM Interactive Training Division for

Skills Development Project

75

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting Identifying My Equipment Step 1: Start Norton SystemWorks Double-click the Norton SystemWorks icon located on the desktop. You can also click the Start button, then Programs, then Norton SystemWorks, then Norton SystemWorks. Step 2: Choose Troubleshoot Submenu On the left side of the screen are the menu items. Click the Norton Utilities menu and then the Troubleshoot submenu. This will give you access to four different utilities. Step 3: Execute System Information Click on the System Information menu located on the right side of the window. This will start the program. This program will give you a list of everything that you need to know about your computer and some things you don't. It may be a helpful thing to know if you ever want to upgrade certain components. Step 4: View the Information There are nine tabs located across the top of the window. Click on the tab that you want to find out information about and it will be displayed. The nine tabs are System, Display, Printer, Memory, Drive, Input, Multimedia, Network, and Internet .

Developed by IDM Interactive Training Division for

Skills Development Project

76

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting Anti-Virus Software 1) • • • • •

List the New features of Norton Antivirus software. List the system requirements of Norton Antivirus . Install Norton . Update manually downloading the definitions from the web. Configure Live updates.

2) CONFIGURING MCAFEE TO AUTOMATICALLY UPDATE AND SCAN HARD DRIVE: • • • • • •

Go to the Windows “Start” button. The console should be located at: Programs à Network Associates à Virus Console Once it is open, double click on “Auto Upgrade”. When the “Task Properties” box opens click on the “Schedule” tab at the top. Choose “Enable”, “Weekly” Then choose a time when you want your computer to upgrade to the newest version. This one is set for 2:00 on Wednesdays and should be set to update once a week.

Developed by IDM Interactive Training Division for

Skills Development Project

77

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting

SKILLS DEVELOPMENT PROJECT Ministry of Tertiary Education & Training

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting Assignments 211

Developed by Interactive Training Division IDM Computer Studies (Pvt) Ltd. http://www.idm.edu

Developed by IDM Interactive Training Division for

Skills Development Project

78

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting

ASSIGNMENT 1 Safety from Statis Electricity Many of the components making up the motherboard are susceptible to ESD, as a necessary precaution always wear a grounded wrist strap and if the motherboard is to be worked on out of the computer chassis, place the board on a grounded rubber mat. These precautions should ensure that no extraneous static voltages are inadvertently applied to board components. Ensure that motherboard documentation and layout details are on hand while working on the board. You should check to make sure that the board layout is the same as the one you are working on before removing any cables or items from the motherboard. To remove a motherboard, first remove the mains power cable. Then remove all external cables to board connectors. Remove all other parts obstructing clear access to the board fixings; such as power supply, expansion cards, bus extenders and chassis bars. Note down where each item was removed and any specific details; such as which slot an expansion card was removed from. Before removing any set of cables, ribbon connector or wire going to the motherboard, note their colour, distinguishing features and their orientation with board connectors and pins. Be sure to note where the other end of the cable, wire or ribbon is also attached for reference. This will ensure that all connectors can be returned to their previous location correctly. It may be necessary to remove a processor cooling fan. Either choose to just remove the supply to the internal power, leaving the fan in place, or determine how the fan is attached to the processor heat conducting fitting. Often there are several screws located in the cooling fins which you will need to remove before the fan unit can be taken out. Once the complete board can be viewed, note down any chip switch settings and the configuration of jumpers. Moving the board could dislodge one or several jumpers or switches, take your time. Physically the board is quite strong when mounted in the computer. Depending on the motherboard design, there will be a mix of small plastic pillars supporting the board and a number of screws to give a firm fitting and to ensure a good electrical connection to the chassis metalwork. By raising the motherboard from the chassis in this way, none of the electrical contacts resulting from the soldered components can short circuit through the chassis metalwork.

Developed by IDM Interactive Training Division for

Skills Development Project

79

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting Task 1 Discuss that how EMI and ESD harmful to your computers.

Task 2 Prepare documentation about your plan. Including: • Prevention tools and the way you should use them. • Justify how practical your proposals Propose a better EMI prevention procedure that you can follow when you are repairing a computer Prepare documentation about your plan.

Task 3 Discuss your idea what kind of EMI and ESD prevention methods that can be used • • •

By the manufacture to designing PCB s By the technician when he is repairing or assembling By the user while that person is working on it.

Developed by IDM Interactive Training Division for

Skills Development Project

80

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting

ASSIGNMENT 2 Computer Performances You are the administrator of four Windows 2000 Server computers in the sales department. Each server has a single Pentium III-600 processor, 192 MB of RAM, and a single 30-GB hard disk. All computers have 100-Mbps network adapter cards. Users in the sales department report that when they attempt to access files or submit print jobs to a server named ServerA, performance becomes very slow. You use system Monitor to monitor ServerA and discover the information that is shown in the following table:

1. List the Minimum hardware requirement for a. b. c. d.

Windows 2000 professional Windows 2000 server Windows 2000 advanced server Windows 2000 Data center server.

2. List the recommended hardware requirements for above operating systems. 3. What is symmetric multiprocessing? 4. Discuss the ways that you can improve the performances in your Server A. 5. How your hard disk performance can effect to the performance of your machine?

Developed by IDM Interactive Training Division for

Skills Development Project

81

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting

ASSIGNMENT 3 Troubleshooting Tools Microsoft Diagnostics Software utility named msd.exe that was included with Microsoft Windows 3.x that listed computer system information. Below is a listing of information available through Microsoft diagnostics: • • • • • • • • • • • • •

Computer brand and processor information Memory (Total, EMS, and XMS) Video (Type such as VGA and manufacturer) Network Operating System versions Type of Mouse if installed Disk drives (and partitions) LPT ports COM ports IRQ status TSR programs Device drivers Other adapters

Download the MSD.EXE from ftp://ftp.microsoft.com/softlib/mslfiles/msdzip.exe Double Click on it and Press “Y” Check your systems above configurations.

How to Generate MSD Reports An MSD report is a diagnostics report that lets us know what system type you have and how it is setup. To run an MSD report, go to the C:\WINDOWS> prompt and type MSD. Once in the diagnostics: 8. Press Alt F to access the file menu 9. Press P for Print Report 10. Press the space bar to place an X in the Report All column 11. Press Enter to continue with the report 12. Type in your information using the TAB key to move to the next line. DO NOT PRESS ENTER UNTIL YOU HAVE COMPLETED ALL INFORMATION. (If you do you will either need to rerun the report or include all customer information on a sheet with your report). 13. Press Enter once you complete customer information. 14. Press Alt F again and X to exit the MSD program .

Developed by IDM Interactive Training Division for

Skills Development Project

82

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting

Device Manager First introduced with the release of Microsoft Windows 95 the Windows device manager is a program that allows a user to view hardware devices and their status. Device manager is available in Microsoft Windows 95, Windows 98, Windows ME, Windows 2000 and Windows XP. To start Device Manager: 4. Click Start, and then click Control Panel. 5. Click Performance and Maintenance, and then click System. 6. Click the Hardware tab, and then click Device Manager.

Troubleshooting Information If there is a problem with a device, it is listed in the hardware tree. Also, the problem device has a symbol that indicates the type of problem: A black exclamation point (!) on a yellow field indicates the device is in a problem state. Note that a device that is in a problem state can be functioning. A problem code explaining the problem is displayed for the device. A red "X" indicates a disabled device. A disabled device is a device that is physically present in the computer and is consuming resources, but does not have a protectedmode driver loaded. A blue "i" on a white field on a device resource in Computer properties indicates that the Use automatic settings feature is not selected for the device and that the resource was manually selected. Note that this does not indicate a problem or disabled state.

A green question mark "?" in Device Manager means that a compatible driver for this device is installed, indicating the possibility that all of the functionality may not be available. Note that this applies only to Windows Millennium Edition (Me). NOTE: Some sound cards and video adapters do not report all of the resources that they use to Windows. This can cause Device Manager to show only one device in conflict, or no conflicts at all. This can be verified by disabling the sound card, or by using the standard VGA video driver to see if the conflict is resolved. Note that this is a known problem with S3 video adapters and 16-bit Sound Blaster sound cards, or those sound cards that are using Sound Blaster emulation for Sound Blaster compatibility.

Developed by IDM Interactive Training Division for

Skills Development Project

83

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting When you double click a specific device in Device Manager, you see a property sheet. The property sheet has a General tab. NOTE: Some devices may have other tabs besides the General tab. Not all property sheets have the same tabs; some devices may have a Resources tab, Driver tab, and Settings tab, or some combination of these. At the top of the property sheet, there is a description of the device. When you click the Resources tab, the window in the middle of the tab indicates which resource types are available for the selected device. The list box at the bottom contains a Conflicting device list. This list indicates a conflict with an error code. For example, to edit the Input/Output Range setting: 4. Click the Use automatic settings check box to clear it. 5. Click Change Setting. 6. Click the appropriate I/O range for the device. NOTE: To disable a device in Device Manager, right-click the device, and then click Disable.

Control Panel Applets The control panels in Windows contain many of the operating system's important settings. You should be familiar with what options can be located in each of the control panels and how to change them. The best way to learn is just to browse the control panels on your computer. Below is a list of the more important Windows control panels. Control panels are named slightly differently in every version of Windows, but the options are generally similar.

Add New Hardware Also called Add Hardware. This control panel is used for adding new hardware. Often, Windows will automatically detect new hardware and guide you through the installation process. If it does not, use this control panel to install the hardware.

Developed by IDM Interactive Training Division for

Skills Development Project

84

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting Let the Add New Hardware Wizard resolve your device problems If you are having problems with a particular device after installing Windows 98 or other software, try removing it and then let Windows 98 reinstall the device. Here's how to do it: 6. On the Start menu, point to Settings, point to Control Panel, and then double-click the System icon. 7. Click the Device Manager tab. (The problem category should automatically open and a symbol should indicate which device is faulty. If it's not working properly, there will be a yellow circle with a black exclamation point inside it; if it's not working at all, there will be a red X.

8. Click once on the problem item to highlight it, and then click Remove. 9. During start up, Windows 98 should detect as missing the device you just removed and automatically run the Add New Hardware Wizard. If you recently downloaded new drivers from any of your hardware manufacturers’ sites, or from Windows Update, be sure to use the wizard's Have Disk option to ensure that Windows 98 installs the new drivers and not any old ones. 10. Hint: When you download new drivers from hardware manufacturers or Windows Update, copy them to a floppy disk and label them. This way, if you ever need to re-install them, and don't have access to the Internet, they are right where you need them.

Add/Remove Programs This control panel is the appropriate place to uninstall programs that did not come with their own uninstaller. Simply deleting files or folders is not a good way to remove an unwanted program. This control panel also allows you to control which Windows Components are installed - you can free up resources by removing unnecessary components .

To add a program from a CD or floppy disk 4. Open Add/Remove Programs in Control Panel. 5. Click Add New Programs, and then click CD or Floppy. 6. Follow the instructions on your screen.

Developed by IDM Interactive Training Division for

Skills Development Project

85

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting Note •

To open a Control Panel item, click Start, point to Settings, click Control Panel, and then double-click the appropriate icon.

•

When using Add/Remove Programs, you can install only programs that were written for Windows operating systems.

•

When you open a program, or try to perform a task within a program, you may see a dialog box indicating that the program is being installed or updated by Windows Installer. This can occur if your administrator has set up the program to install this way, if program files have been deleted or corrupted, or if you are trying to use a program feature that was not installed during setup. If the program was installed from a CD-ROM, or if you are no longer connected to the network, Windows Installer may ask you for the CD-ROM. When Windows Installer finishes, the program or feature you are trying to use starts

To change or remove a program 4. Open Add/Remove Programs in Control Panel. 5. Click Change or Remove Programs, then click the program you want to change or remove. 6. Click the appropriate button: •

To change a program, click Change/Remove or Change.

•

To remove a program, click Change/Remove or Remove.

Caution •

When you click Change/Remove, some programs may be removed without prompting you further.

Note •

To open a Control Panel item, click Start, point to Settings, click Control Panel, and then double-click the appropriate icon.

•

When using Add/Remove Programs, you can remove only programs that were written for Windows operating systems. For other programs, check the documentation to see if other files (such as .ini files) should be removed.

•

When you open a program, or try to perform a task within a program, you may see a dialog box indicating that the program is being installed or updated by Windows Installer. This can occur if your administrator has set up the program to install this way, if program files have been deleted or corrupted, or if you are trying to use a program feature that was not installed during setup. If the program was installed from a CD-ROM, or if you are no longer connected to the network, Windows Installer may ask you for the CD-ROM. When Windows Installer finishes, the program or feature you are trying to use starts. Developed by IDM Interactive Training Division for

Skills Development Project

86

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting To add or remove a Windows 2000 component 4. Open Add/Remove Programs in Control Panel. 5. Click Add/Remove Windows Components. 6. Follow the instructions in the Windows Components wizard. Note •

You must be logged on as an administrator or a member of the Administrators group in order to complete this procedure. If your computer is connected to a network, network policy settings may also prevent you from completing this procedure.

•

To open a Control Panel item, click Start, point to Settings, click Control Panel, and then double-click the appropriate icon.

•

Certain Windows Components require configuration before they can be used. If you installed one or more of these components, but did not configure them, when you click Add/Remove Windows Components, a list of components that need to be configured is displayed. To configure a component, click Configure, and then follow the instructions on the screen. To add a new component, click Components, and follow the instructions in the Windows Components wizard.

Display This control panel allows you to control the appearance of your computer. You can change your background wallpaper and screen saver, select the display resolution and change the color scheme. 5. To access display settings click on Start>Settings>Control Panel. 6. Select "Display" and choose the Settings Tab. 7. Do not use 256 colors as your graphics setting. You should choose to use at least "high color". 8. Using 256 colors can result in colors not being displayed properly.

Modems Also called Phone and Modem Options. Here, you can configure your modem settings and dialing options (including configuring for long distance or calling card dialing).

Network Also called Network Connections. This control panel allows you to configure your network settings. Please see the section on Networking for Princeton-specific configuration information. Developed by IDM Interactive Training Division for

Skills Development Project

87

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting Configuring the Network Adapter Software 6. Open the Control Panel (click on Start --> Settings) and double-click on the Network icon. 7. You need to run Add/Remove Programs and Windows Setup, which are both available in the Control Panel window, to install network support. 8. Click on the Add button and double-click on Adapter. 9. Select your Ethernet adapter manufacturer and type from the list. If you wish to use a network adapter that is not listed, contact the manufacturer for a Windows compliant driver. 10. The Network Control Panel will display several protocols and clients, such as Client for Microsoft Networks, Client for NetWare Networks, IPX/SPXcompatible Protocol, and NetBEUI.

Installing the TCP/IP Protocol 6. Click on the Add button from the Network Control Panel again to add a new Protocol. 7. Select Manufacturer Microsoft and Network Protocol TCP/IP. 8. Click OK to close the Network Control Panel. 9. Unless you did a full installation of Windows, you will be prompted for the Windows installation disks. In some cases, the installation will require the Windows disks even if you did a full installation. Be sure to use the appropriate version of the Windows CD. New hard disks may come with the "B" version (OSR2) of Windows 95 or with Windows 98. Mixing versions can render the PC unbootable. 10. When the installation program finishes copying the files, restart your PC

Configuring TCP/IP Properties 8. Open the Control Panel (click on Start -> Settings) and double-click on the Network icon. 9. In the Network dialog box, click the Configuration tab if it isn't already selected. 10. In the list of network components installed, select the entry for the TCP/IP protocol and your network adapter Then, click the Properties button. 11. Click on the IP Address tab (if it isn't already selected) and verify that the default Obtain an IP address automatically is selected. 12. Click on the DNS Configuration tab and enter the following information: 1. Click on the Enable DNS option button. 2. In the Host field, enter the host name for your PC which you received during registration 3. In the Domain field, enter: dur.ac.uk (For this contact your network Administrator) 4. In the DNS Server Search Order field, enter the following IP addresses, clicking the Add button after entering each one: 203.115.0.19 and 203.115.0.1(For this contact your network Administrator) 5. In the Domain Suffix Search Order, enter: dur.ac.uk (For this contact your network Administrator) Developed by IDM Interactive Training Division for

Skills Development Project

88

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting

13. Click OK, and then click OK in the Network dialog box. 14. Click Yes when prompted to restart your PC.

Users Also called User Accounts. This control panel is used for creating and modifying local user accounts, setting and changing passwords.

8. Login as Administrator. 9. Select Start/Programs/Administrative Tools/Computer Management. 10. From the Computer Management snap-in open the System Tools/Local Users and Groups node. Right-click on the Users node and select New User…. The New User dialog box should appear. 11. Enter your username (first initial lastname, e.g. dglazer), full name and password/confirm password. 12. Uncheck the default selection of “User must change password at next logon”. 13. Press Create button. 14. Press Close to exit the window. The new user now appears in the right pane of the Computer Management snap-in.

Power Management Also called Power Options. In this control panel are the options for power saving features (which are especially important on a laptop). You can have your computer go into "sleep" or "hibernate" mode and shut off its monitor or hard drive, saving power when you are away from the computer. 10. Select Start > Settings > Control Panel from the Start Menu. 11. Double click the Display icon in the Control Panel window. 12. In the Display Properties dialog, click the Screen Saver tab, then click the Power button in the Energy saving features of monitor box. 13. Under Power Schemes, select Home/Office Desk. Note: Some of the options shown here, such as System Standby and System Hibernates, may not appear on your computer. If this is the case, simply skip the steps that do not apply to you. The options available may vary depending on your computer's capabilities. 14. Set Turn Off Monitor after 10 minutes. 15. Set Turn Off Hard Drives to Never. 16. Set System Standby to Never. 17. Set System Hibernates to Never. 18. Click OK.

Developed by IDM Interactive Training Division for

Skills Development Project

89

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting System This control panel contains the system's general information. It tells you the exact version of your operating system as well as how much RAM the system has. It also provides a Device Manager for viewing what hardware or virtual devices may be causing problems (the Device Manager also allows you to update hardware drivers). More advanced system configuration tools can be found in this control panel, though changing them is not recommended without a full understanding of their effects.

System Configuration Editor Configuration Editor allows you to examine and edit your system files (config.sys, win.ini, etc.) all in one place with a clean, orderly, tabbed document interface. Just click on the tab to go from one file to another. You already have System Configuration Editor (sysedit.exe), which comes with windows, but it uses the awkward multi-window approach. Compare the two and you'll see why Configuration Editor is easier to use. 1) 2) 3) 4)

Click the "Start" button. Select Run from the pop-up menu Type SYSEDIT in the white text box A new window will open which will have within it four other windows, each one containing a file. 5) You can simply click on the title of any of the windows and that will change the focus to that window and then by clicking anywhere within that window you can modify the contents. 6) If any changes were made, the computer will present you with a warning pop-up window asking if you want to save the changes. You click on the "Yes" button to continue. At that time the files will be saved and the sysedit program will close. 7) The changes will take effect the next time you reboot your computer. A similar method for making changes to the above files from within DOS is to use the EDIT function. This would be done by going to a DOS prompt and typing the command EDIT autoexec.bat <enter> A DOS based window would open allowing you to make changes. When you are done you would use a similar method of exiting by selecting File Exit from the top menu.

Developed by IDM Interactive Training Division for

Skills Development Project

90

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting

PC Tools List and experience third party tools for 7. Disk defragmenting 8. Disk Cleaning 9. Disk Partitioning. 10. Software and operating system deploying. 11. Operating system restoring. 12. Back up FDISK is often the tool of choice for ex-DOS users when managing drive partitions. This tool works great as long as you are working with all primary partitions or only FAT, FAT32, and OS/2's HPFS. FDISK is not even able to recognize NTFSformatted extended partitions. So, if you need to delete such a partition, you either need to have access to a Windows NT, Windows 2000, or Windows XP OS on the same system as the hard drive in question, and boot into the setup routines of one of these three OSes to use the text-based partition configuration tool, or use a third party tool. I've already mentioned Partition Magic, but there is another tool you may want to look at: DELPART. DELPART is a DOS based tool from Windows NT 3.51; you can find it floating around the Internet with a quick search on "delpart". This too can delete any and all partitions on a hard drive, thus making way for easy repartitioning and new OS installation. • •

Use FDISK to partition a Hard disk Use DELPART to partition a Hard disk

Norton Utilities Norton Utilities is a group of programs that let you do everything from deleting items so that they cannot be recovered to watching your system for problems. It will find and fix problems associated with hardware or software, help you recover files you accidentally erased, and monitor your system at all times. This series will explain to you how to accomplish all of these tasks and more. Experience the following Norton utilities. Install Norton utilities Set Up Your Options Step 1: Start Norton System Works Double-click the Norton System Works icon located on the desktop. You can also click the Start button, then Programs, then Norton SystemWorks, then Norton SystemWorks. Step 2: Click Options Click the Options button and then choose the Norton Utilities submenu. This will take you to the options screen for setting up the software. Step 3: Tabs There are six different tabs that you can set options for. The tabs are General Settings, Startup Programs, WipeInfo Settings, System Check Scheduler, Recycle Bin, and Norton Protection. Click the tab for the one that you want to change the options for. Developed by IDM Interactive Training Division for

Skills Development Project

91

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting Step 4: General and Startup The General tab lets you specify if you want to see introductions and splash screens before starting any of the programs. The Startup tab lets you decide which of the programs will be run on startup. Step 5: WipeInfo and Norton Protection The WipeInfo tab sets up what type of deletion you want when you delete a file. You can set it up to write over the information once or several times. The Norton Protection tab is used to set the number of days before files that were deleted under DOS will be protected. Step 6: Recycle Bin and Scheduler The Recycle Bin tab lets you decide what will open when you double-click the recycle bin and also what the recycle bin will look like on your desktop. The System Check Scheduler tab lets you set up when you certain events to be performed.

Conducting a Checkup Step 1: Start Norton SystemWorks Double-click the Norton SystemWorks icon located on the desktop. You can also click the Start button, then Programs, then Norton SystemWorks, then Norton SystemWorks. Step 2: Choose Find & Fix Submenu On the left side of the screen are the menu items. Click the Norton Utilities menu and then the Find and Fix Problems submenu. This will give you access to four different utilities. Step 3: Execute Norton System Check Click on the Norton System Check menu located on the right side of the window. This will start the program. Step 4: Start Diagnosing Put a checkmark into each of the categories that you want the software to check. When you've finished deciding which categories click the Next button and the software will start analyzing your system. Step 5: Fix Problems After the software has finished scanning the system, click the Finish button and a list of the problems that were found will be displayed. To repair the items, highlight the ones that you want to repair and click the Repair button. If you want to repair each item individually, double-click one of the items and you'll be asked if you want to repair each item or have the software do it automatically.

Developed by IDM Interactive Training Division for

Skills Development Project

92

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting Finding Windows Problems Step 1: Start Norton SystemWorks Double-click the Norton SystemWorks icon located on the desktop. You can also click the Start button, then Programs, then Norton SystemWorks, then Norton SystemWorks. Step 2: Choose Find & Fix Submenu On the left side of the screen are the menu items. Click the Norton Utilities menu and then the Find and Fix Problems submenu. This will give you access to four different utilities. Step 3: Execute Norton WinDoctor Click on the Norton WinDoctor menu located on the right side of the window. This will start the program. This program will check the windows registry file to ensure that all of the entries are correct. Step 4: Choose Tests to Run You can decide to run all of the tests which are the recommended option or you can choose to only run some of the tests. You make your choice. If you decide to choose the tests, remove the checkmark from the tests that you don't want to perform. Step 5: Fix Found Problems If any problems were found to exist during the testing they will be shown to you when you click the Finish button. To fix a problem, highlight the problem that you want to fix and click the Repair button. The software will automatically make the repairs for you.

Diagnose and Repair Step 1: Start Norton SystemWorks Double-click the Norton SystemWorks icon located on the desktop. You can also click the Start button, then Programs, then Norton SystemWorks, then Norton SystemWorks. Step 2: Choose Find & Fix Submenu On the left side of the screen are the menu items. Click the Norton Utilities menu and then the Find and Fix Problems submenu. This will give you access to four different utilities. Step 3: Execute Norton Disk Doctor Click on the Norton Disk Doctor menu located on the right side of the window. This will start the program. This program will test the integrity of the hard drive. Step 4: Set Options By clicking the Options button, you can set what will happen when the program runs. There are four tabs available. The most important one is the General tab. The other three tabs are for appearances, how many times the disk will be scanned, and tests that should be skipped. On the General tab, you need to decide about your repair options. You can have the software automatically fix the problems, skip the problem, or prompt you for action to take.

Developed by IDM Interactive Training Division for

Skills Development Project

93

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting Step 5: Diagnose the Disk Click the Diagnose button and the process will begin. A list of what is being checked will be displayed and a checkmark will be put next to the category when the check has been completed. Step 6: Viewing Results After the completion of the scanning, a list of the results that were found will be displayed. If there are any problems, follow the instructions for fixing the problem.

Restoring Deleted Files Step 1: Start Norton SystemWorks Double-click the Norton SystemWorks icon located on the desktop. You can also click the Start button, then Programs, then Norton SystemWorks, then Norton SystemWorks. Step 2: Choose Find & Fix Submenu On the left side of the screen are the menu items. Click the Norton Utilities menu and then the Find and Fix Problems submenu. This will give you access to four different utilities. Step 3: Execute UnErase Wizard Click on the UnErase Wizard menu located on the right side of the window. This will start the program. This program will let you recover any files that have been deleted. It may even be able to recover files that have been deleted from the Recycle Bin. Step 4: Find Files When you first bring up the UnErase Wizard, you'll have to choose what types of files you want the software to look for. You can choose Recently deleted files, Protected files, and Files meeting your criteria. When you've decided this, click the Next button. Step 5: Choose a File Highlight the file that you want to recover. Once you've highlighted this file, click the Recover button. If you want to recover more files or try to find files that meet certain criteria click the Next button to continue with the process. Undoing Fixes Step 1: Start Norton SystemWorks Double-click the Norton SystemWorks icon located on the desktop. You can also click the Start button, then Programs, then Norton SystemWorks, then Norton SystemWorks. Step 2: Choose Find & Fix Submenu On the left side of the screen are the menu items. Click the Norton Utilities menu and then the Find and Fix Problems submenu. This will give you access to four different utilities. Step 3: Run a Program Norton System Check, Norton WinDoctor, and Norton Disk Doctor each have the ability to undo fixes that have been made. Execute the one that you want to undo the changes in. Developed by IDM Interactive Training Division for

Skills Development Project

94

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting Step 4: History Report When the first screen is displayed, click the Cancel button. You'll know be shown the problems screen. Click on the History icon and the history report will be displayed. This shows all of the problems that have been fixed in the past. Step 5: Undo the Fix Highlight the problem that you want to undo and click the Undo icon. You'll be asked if you're sure you want to undo the fix. If you do want to undo it, click the Yes button. If not, click the No button.

Speeding Up Your Computer Step 1: Start Norton SystemWorks Double-click the Norton SystemWorks icon located on the desktop. You can also click the Start button, then Programs, then Norton SystemWorks, then Norton SystemWorks. Step 2: Click Improve Performance On the left side of the screen are the menu items. Click the Norton Utilities menu and then the Improve Performance submenu. This will give you access to four different utilities. Step 3: Execute Speed Disk Click on the Speed Disk menu located on the right side of the window. This will start the program which will help defragment your hard drive and move the files around so that your computer will operate more efficiently. Step 4: Recommended Action After the program is started, the hard drive will be analyzed. The software will let you know what was found and will show you how fragmented the drive is and give you a recommendation as what should be done. Choose which option you want and click the Start button when you're ready to defragment your drive. Depending on the size of your hard drive and the amount of fragmentation, it may take a while for the entire process to complete.

Optimizing the Registry File Step 1: Start Norton SystemWorks Double-click the Norton SystemWorks icon located on the desktop. You can also click the Start button, then Programs, then Norton SystemWorks, then Norton SystemWorks. Step 2: Click Improve Performance On the left side of the screen are the menu items. Click the Norton Utilities menu and then the Improve Performance submenu. This will give you access to four different utilities. Step 3: Execute Optimization Wizard Click on the Norton Optimization Wizard menu located on the right side of the window. This will start the program. This program will look at the registry file and try to minimize its size and rearranging its structure so as to increase the access speed. Developed by IDM Interactive Training Division for

Skills Development Project

95

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting Step 4: Optimization Choices The wizard will walk you through the choices for optimizing the files. You can optimize two files, the swap file and the registry file. Click the Next button and choose if you want to optimize these files. Step 5: Optimize the System After you've chosen which of the two options to optimize you'll need click the Reboot button. After the files have been optimized, the system will automatically reboot itself to finish the process. Make sure that you've saved all of your files before clicking the Reboot button

Add Sensor to System Doctor Step 1: Start Norton SystemWorks Double-click the Norton SystemWorks icon located on the desktop. You can also click the Start button, then Programs, then Norton SystemWorks, then Norton SystemWorks. Step 2: Choose Preventive Maintenance On the left side of the screen are the menu items. Click the Norton Utilities menu and then the Preventive Maintenance submenu. This will give you access to four different utilities. Step 3: Execute Norton System Doctor Click on the Norton System Doctor menu located on the right side of the window. This will start the program. This program will continuously monitor your computer for problems and let you know before they happen. Step 4: Sensor List Click on the Sensors menu and choose the category that you want to add. There are six different categories that you can add from. When you move to a submenu, you'll have further choices to make. Choose the one that you want and it will be added to the Norton System Doctor window.

System Doctor Sensor Editing Step 1: Start Norton SystemWorks Double-click the Norton SystemWorks icon located on the desktop. You can also click the Start button, then Programs, then Norton SystemWorks, then Norton SystemWorks. Step 2: Choose Preventive Maintenance On the left side of the screen are the menu items. Click the Norton Utilities menu and then the Preventive Maintenance submenu. This will give you access to four different utilities. Step 3: Execute Norton System Doctor Click on the Norton System Doctor menu located on the right side of the window. This will start the program. This program will continuously monitor your computer for problems and let you know before they happen. Developed by IDM Interactive Training Division for

Skills Development Project

96

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting Step 4: Choose the Sensor Right-click the sensor that you want to change the properties for. You'll get a menu of selections. Choose the top menu item labeled Properties. and you'll get the properties box. You'll now be able to change the settings for that sensor. Step 5: Other Menu Items When you right-click a sensor there are several different menu items. Update the status of the sensor immediately. If you want to remove a sensor, click the Remove menu. To find out information about the sensor click the Sensor Information menu. Some of the sensors have programs associated with them. If this sensor is one, you can click the Open program name menu item.

Permanently Deleting Data Step 1: Start Norton SystemWorks Double-click the Norton SystemWorks icon located on the desktop. You can also click the Start button, then Programs, then Norton SystemWorks, then Norton SystemWorks. Step 2: Choose Preventive Maintenance On the left side of the screen are the menu items. Click the Norton Utilities menu and then the Preventive Maintenance submenu. This will give you access to four different utilities. Step 3: Execute Norton WipeInfo Click on the Norton WipeInfo menu located on the right side of the window. This will start the program. This program will delete files from your computer so that you can't recover them, even with undo. You can also clear the free space on your hard drive. Step 4: Choose the Type of Deletion You've got three choices as to what you want to wipe clean. You can choose either files, folders, or free space. When you make your choice click the Next button to continue with the process. Step 5: Select Files, Folders or Space Depending on the choice you made in the previous step, you'll need to choose which files or folders to delete. If you had chosen free space you need to decide which hard drives to clean. Step 6: Wipe Options Choose the type of wipe that you want to accomplish. The Fast Wipe will write over the space once. The Government Wipe will write over the space with digits the specified number of times. The more times that the space is written over, the harder it would be to recover the file.

Developed by IDM Interactive Training Division for

Skills Development Project

97

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting Imaging Your Drive Step 1: Start Norton SystemWorks Double-click the Norton SystemWorks icon located on the desktop. You can also click the Start button, then Programs, then Norton SystemWorks, then Norton SystemWorks. Step 2: Choose Preventive Maintenance On the left side of the screen are the menu items. Click the Norton Utilities menu and then the Preventive Maintenance submenu. This will give you access to four different utilities. Step 3: Execute Image Click on the Image menu located on the right side of the window. This will start the program. This program takes a picture of your hard drive and keeps that information. This information is used when trying to rebuild deleted files or if there is a problem with the structure of your folders. Step 4: Setting Options Click the Options button and you'll be taken to the options screen. Here you can set the software up to create an image every time that the computer starts. You also can tell it what drives to image. Step 5: Create an Image Choose which drives you want to image and click the Image button. The software will start creating the image and a progress bar will be displayed at the bottom of the window showing the status.

Diagnose Hardware Problems Step 1: Start Norton SystemWorks Double-click the Norton SystemWorks icon located on the desktop. You can also click the Start button, then Programs, then Norton SystemWorks, then Norton SystemWorks. Step 2: Choose Troubleshoot Submenu On the left side of the screen are the menu items. Click the Norton Utilities menu and then the Troubleshoot submenu. This will give you access to four different utilities. Step 3: Execute Norton Diagnostics Click on the Norton Diagnostics menu located on the right side of the window. This will start the program. This program will complete eleven different tests to analyze your hardware for possible problems. Step 4: Conducting the Tests On the left side of the window is a section that lists all of the tests that are available. If you want to conduct all of the tests, highlight Do All Tests and click the Test button. If you only want to conduct a test on a specific piece of hardware, highlight that hardware item and click the Test button. Step 5: View the Results During the course of the testing, you'll see the results displayed in the window. You can see what test was performed and if the component passed the test. Developed by IDM Interactive Training Division for

Skills Development Project

98

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting Identifying My Equipment Step 1: Start Norton SystemWorks Double-click the Norton SystemWorks icon located on the desktop. You can also click the Start button, then Programs, then Norton SystemWorks, then Norton SystemWorks. Step 2: Choose Troubleshoot Submenu On the left side of the screen are the menu items. Click the Norton Utilities menu and then the Troubleshoot submenu. This will give you access to four different utilities. Step 3: Execute System Information Click on the System Information menu located on the right side of the window. This will start the program. This program will give you a list of everything that you need to know about your computer and some things you don't. It may be a helpful thing to know if you ever want to upgrade certain components. Step 4: View the Information There are nine tabs located across the top of the window. Click on the tab that you want to find out information about and it will be displayed. The nine tabs are System, Display, Printer, Memory, Drive, Input, Multimedia, Network, and Internet .

Developed by IDM Interactive Training Division for

Skills Development Project

99

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting Anti-Virus Software 1) • • • • •

List the New features of Norton Antivirus software. List the system requirements of Norton Antivirus . Install Norton . Update manually downloading the definitions from the web. Configure Live updates.

2) CONFIGURING MCAFEE TO AUTOMATICALLY UPDATE AND SCAN HARD DRIVE: • • • • • •

Go to the Windows “Start” button. The console should be located at: Programs à Network Associates à Virus Console Once it is open, double click on “Auto Upgrade”. When the “Task Properties” box opens click on the “Schedule” tab at the top. Choose “Enable”, “Weekly” Then choose a time when you want your computer to upgrade to the newest version. This one is set for 2:00 on Wednesdays and should be set to update once a week.

Developed by IDM Interactive Training Division for

Skills Development Project

100

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting

ASSIGNMENT 4 VGA Troubleshooting You install Windows 2000 Professional on a computer that has a non-plug and play video adapter. You want to configure the video adapter to use 16-bit color and 1024 x 768 resolution. The color setting for the video adapter is set to 16 colors, and you cannot change that setting. The video adapter properties are shown in the (default monitor) and VGA properties dialog box in the exhibit.

1. 2. 3. 4.

List the types of display adapters. Discuss that how you install VGA card driver. (In any platform) Discuss how the display frequency of your monitor effecting to ergonomics. Discuss the matter in the above scenario and discuss that how you troubleshoot that.

Developed by IDM Interactive Training Division for

Skills Development Project

101

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting

ASSIGNMENT 5 Obtaining and Calculating Power Supply Data Over time, there have been at least six different standard power supplies for personal computers. Recently, the industry has settled on using ATX-based power supplies. ATX is an industry specification that means the power supply has the physical characteristics to fit a standard ATX case and the electrical characteristics to work with an ATX motherboard. PC power-supply cables use standardized, keyed connectors that make it difficult to connect the wrong ones. Also, fan manufacturers often use the same connectors as the power cables for disk drives, allowing a fan to easily obtain the 12 volts it needs. Color-coded wires and industry standard connectors make it possible for the consumer to have many choices for a replacement power supply.

Objective : Determine the power output required for a computer. This task requires: • a computer to be shared between two students; •

a grounded rubber mat to place the computer on would be useful with some clear working area in which to place removed items from the computer.

•

Students will need to remove at least one panel from the computer case in order to access the power supply unit.

•

Each pair of students should then: o note down all devices within the computer that require power (this list will be used as part of the Student Exercises outside class to determine each device’s power needs according to reference articles). o using the voltage and maximum loading figures quoted oil the PSU labeling, calculate the total power output (using the schema shown in the visual which is repeated below for convenience). Compare to the rated value of the PSU.

Developed by IDM Interactive Training Division for

Skills Development Project

102

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting

SKILLS DEVELOPMENT PROJECT Ministry of Tertiary Education & Training

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting Case Studies 211

Developed by Interactive Training Division IDM Computer Studies (Pvt) Ltd. http://www.idm.edu

Developed by IDM Interactive Training Division for

Skills Development Project

103

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting

CASE STUDY 1 Technical Support Introduction You are the senior technical support manager at a large multinational company with over 5,000 users online at any onetime. Over the last few months the workload of the support department has increased dramatically following the introduction of several new systems. As a result the users have to wait longer and longer in order to get their outstanding problems resolved. This is leading to frustration and the management is concerned that productivity is being adversely affected. In the circumstances it has been decided that a totally new approach to providing technical support to users is required and the latest technology should be employed wherever possible to reduce the waiting times and speed up responses to problems.

Aims • • •

To produce a feasibility report outlining the case for the installation of a technical support system within the company. To select a suitable solution and to produce a detailed specification. To develop a comprehensive project plan for its implementation.

These three documents (feasibility report, detailed specification and project plan) will form the basis of a presentation to the management in order to convince them that the proposed Solutions are justifiable and practical.

Task 1 Evaluate the benefits of revising the current technical support infrastructure for the company in the form of a feasibility report to include the following: •

An analysis of the basic problems that are likely to be encountered when supporting a large number of online users and to assess potential requirements.

•

A brief overview of current Help Desk technologies (both hardware and software).

•

A coherent argument as to the advantages and possible disadvantages of implementing a computerized Help Desk within the company.

Developed by IDM Interactive Training Division for

Skills Development Project

104

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting Task 2 Using the Internet and any other resources available, carry out research into what Help Desk systems are currently available. Select ONE suitable solution and produce a detailed specification for each of the components (both hardware and software) required to implement a new Technical Support solution. The specification document should include the following: • • •

Your analysis of the requirements. Full details of the system configuration. Estimated costs for the provision of appropriate hardware and software.

Guidance Consult with your tutor during and after familiarizing yourself with the tasks required and producing a formal action plan in order to reach the assignment objective. During the design stages discuss the reasons for the choices you are making with your tutor who may give advice on the advantages and limitations of your approach. Submission Requirements All documentation outlined in the tasks produced by the student should be signed and dated by your tutor.

Developed by IDM Interactive Training Division for

Skills Development Project

105

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting

CASE STUDY 2 PC Upgrading The following equipment will be required: • A PC system with the following minimum specification: • Motherboard with IDE support or separate IDE expansion card • Intel Pentium 120Mhz or equivalent processor • VGA graphics adapter • 32Mb RAM • 500Mb hard disk (with a suitable operating system installed) • floppy disk drive • parallel port • monitor • keyboard • mouse • 1 x CD.ROM drive with appropriate driver disks. • 1 x Motherboard suitable for the proposed processor and memory upgrade. • 1 x Power Supply Unit of suitable wattage for the proposed upgraded system. • 1 x Intel Pentium Ill, Celeron, or AMD processor (minimum 500 MHz See note below. NOTE: Before commencing this practical assignment the tutor/lecturer must ensure that the system unit case is appropriate for the Task in hand. In particular, the tutor/lecturer should check that the motherboards supplied to the candidates are the correct format and that they can be fined into the system units correctly. • •

1 x Windows 95 or 98 CD-ROM master disk. Appropriate driver software for new components fitted to the system.

NOTE: The candidates should work in pairs. In order to avoid any health and safety issues a single candidate should not be allowed to conduct the practical project in isolation.

Assignment You are responsible for providing technical support for a medium sized company which currently has a number of rather old PCs. Rather than replace these with completely new systems it has been decided to upgrade the system units to enable them to run the latest software applications more efficiently. The upgrade to each PC will consist of the installation of faster processors, larger memory and CD-ROM drives. However, in order to perform such an upgrade the motherboard and Power Supply Unit (PSU) will need to be replaced as the existing motherboard is incapable of supporting a higher class of processor.

Developed by IDM Interactive Training Division for

Skills Development Project

106

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting Task 1 Candidates should start by familiarizing themselves with the equipment supplied and producing a formal action plan in order to reach the assignment objective. Notes should be made throughout the project in order to document the procedures carried out.

Task 2 The candidates will be expected to carry out the following procedures within the allotted timescale: • Disassemble the PC system unit and remove the existing motherboard and PSU. • Fit the replacement PSU, motherboard and new processor. • Install new memory modules. • Install the CD-ROM drive. • Reassemble the system unit installing the remaining system components as required. • Connect all peripherals to system unit. • Start the PC and enter the system BIOS. • Adjust any BIOS settings as necessary. • Install any appropriate driver software for the CD-ROM drive. • Use the Windows 95 or 98 master disk to re-install or update any operating system components as necessary. • Test the system to ensure that all components and peripherals (both new and old) are working correctly.

Task 3 Produce a formal project report detailing the Tasks carried out and the procedures followed.

Task 4 Produce suitable test documents printed from each PC s howing the new specification of the system (processor type and speed, amount of memory installed, and CD-ROM drive fitted).

Developed by IDM Interactive Training Division for

Skills Development Project

107

National Diploma in Information & Communication Technology

Computer Maintenance & Troubleshooting Guidance Consult with your tutor/lecturer during and after familiarizing yourself with the equipment supplied and producing a formal action plan in order to reach the assignment objective. During the practical stages discuss the reasons for the choices you are making with your tutor/lecturer who may give advice on the advantages and limitations of your approach. If you have any doubts about the safety aspects of any particular procedures then these should be discussed with your tutor before implementation and noted in your documentation.

Submission Requirements 1. All documentation outlined i.e. a formal action plan of Tasks, a formal project report, and printed test documents produced should be signed and dated by your tutor/lecturer.

2. The main assessment criteria for this practical project will be the successful: 1. upgrading of the PC system. 2. the printout detailing the new system specification. 3. The highly practical nature of the project means that tutors/lecturers must observe the candidates during the exercise in order to be able to carry out a thorough assessment. In addition, the examiner should be responsible for overall safety during the exercise and if necessary take appropriate action to avoid any potential accidents.

Developed by IDM Interactive Training Division for

Skills Development Project

108