Chapter Overview

1. Chapter Overview • Computer Disassembly and Reassembly • Upgrading a Computer

2. Preparing to Work on a Computer • Documentation is key to preparation. • Collect the following before starting a job: • Computer configuration sheet • Computer and motherboard documentation • List of all installed expansion cards • Operating system (OS) documentation • A plan of action that includes a checklist of tasks, tools, and parts

3. Questions to Ask Before Starting a Job • Is this the right computer? • Why am I taking it apart? • Do I have everything necessary to do the job? • Do I need more information before starting the job? • Are there any proprietary hardware components in this machine? • Do any of these tasks require the assistance of a third-party technician?

4. Tools and Components • Assemble a toolkit that contains standard tools and a DOS boot floppy disk. • During planning, ensure that you have all items required. • Have on hand: • The original OS disks • A rescue disk for the version of Microsoft Windows you are working with • The correct utilities for the OS version • Virus-checking utilities, with up-to-date signature files

5. Disassembling a Computer • Removing the computer case gives you access to memory, expansion slots and cards, and the CPU. • Each computer brand has some custom components or layout. • Use the manual and other documentation that came with the computer. • The extent to which you have to disassemble a computer depends on the specific problem or repair.

6. Procedure for Disassembling a Computer • Make a complete backup of necessary OS and working files. • Document the system (hardware and software). • Create a clean work area with plenty of room and light. • Gather all the necessary tools for the job. • Implement all proper safety procedures. • Turn off the computer.

7. Procedure for Disassembling a Computer (Cont.) • Disconnect the power cables. • Wear an antistatic wrist-grounding strap. • Locate the screws for the cover. • Remove the screws. • Remove the cover from the computer. • Document the location of expansion cards and drives.

8. Procedure for Disassembling a Computer (Cont.) • Remove all the cards and place them in antistatic bags. • Document the location and connections for each drive. • Remove the interface and power connection cables. • Remove the drives from their bays. • Remove the motherboard.

9. Reassembling a Computer • Follow the disassembly procedure in reverse order. • Do not force connectors into place. • Do not force expansion cards into the slots. • When removing cables, remember the pin 1 locations. • Connect the cables to the drives before installing the drives in the bays. • Test the system before replacing the cover.

10. Preparing to Upgrade: the Configuration Sheet

11. Memory • As programs and hardware get faster, memory is more important. • Memory upgrades are simple to perform. • Purchasing the right type of memory is critical. • Consider memory chip format, speed, extended data out random access memory (EDO RAM), parity, and cache memory. • Check the motherboard documentation to determine the memory type, population scheme, and location of memory slots. • Two basic formats for memory are single inline memory modules (SIMMs) and dual inline memory modules (DIMMs).

12. SIMM Formats 30-Pin SIMM • Contains memory in 8-bit chunks • A 32-bit processor requires four SIMMs 72-Pin SIMM • Contains memory in 32-bit chunks • A 32-bit processor requires one SIMM

13. DIMM Formats • DIMMs are easier to install than SIMMs. • A “key” or notch cut into one edge prevents incorrect installation. • When you buy a DIMM, you must know the exact memory type. • DIMMs are found in larger memory sizes than SIMMs.

14. Memory Considerations • Memory speed is measured in nanoseconds (one-billionth of a second). • The lower the number, the faster the chip speed. • All chips in the same computer should run at the same speed. • Typical speeds are 50, 60, 70, and 80 nanoseconds. • The motherboard documentation should list the appropriate speed.

15. EDO RAM • EDO RAM can improve read times and overall performance by up to 30 percent. • The chip outputs data from one address while setting up a new address.

16. Parity • Parity is used to check the reliability of data. • Parity requires an additional bit. • Memory can be purchased with or without parity; the cost is higher with parity. • System specifications indicate if parity is required. • Parity and nonparity chips cannot be mixed. • Some systems allow parity to be turned on or off in the basic input/output system (BIOS).

17. Cache Memory • L1 cache is built into the processor and cannot be changed. • L2 cache can be built into the processor or on the motherboard. • Check the motherboard documentation to determine if you can upgrade the L2 cache.

18. Installing a SIMM

19. CPU Upgrades • CPU upgrades are becoming less common. • The first task is to determine if the CPU can be upgraded and which CPU upgrade will work. • The motherboard documentation specifies compatible CPUs. • Check on required BIOS upgrades or jumper settings. • A new motherboard is required for upgrading a 386 to a Pentium or a Pentium to a Pentium III, or for CPUs from different manufacturers.

20. General Procedure for Installing a CPU • Turn off the computer and unplug the power cord. • Disconnect external devices (AC power and monitor power). • Follow the appropriate electrostatic discharge (ESD) safety precautions. • Remove the cover of the computer. • Locate the socket for the CPU on the motherboard. • Remove the old processor.

21. General Procedure for Installing a CPU (Cont.) • Install the new processor by aligning the chip properly. • Set any jumpers or switches on the motherboard. • Reconnect any peripherals (keyboard, mouse, monitor). • Replace the cover and power up the computer. • Make changes to the BIOS, if required, using the complementary metal-oxide semiconductor (CMOS) setup program.

22. Additional Considerations for Installing a New CPU • Some CPU upgrades require installing a new voltage regulator and cooling fan. • In motherboards that support more than one CPU, all CPUs must be of the same type and from the same manufacturer. • Some Pentium II and later motherboards have a special card that is inserted in any empty CPU slot.

23. Expansion Cards • Install an expansion card to add faster video, add more ports, or improve sound quality. • Ensure that the expansion card will work in the system to be upgraded. • Ensure that the appropriate drivers are available for the OS.

24. Considerations for Installing an Expansion Card • Ensure that adding a new card is the most cost-effective way to upgrade. • If no expansion slots are available, free up space by • Replacing single-port cards with one multifunction card • Using a Small Computer System Interface (SCSI) card and a chain of SCSI devices • Using a universal serial bus (USB) if available

25. Considerations for Installing an Expansion Card (Cont.) • Ensure that the card fits in the slot and matches the bus type of the motherboard. • Document available I/O ports and interrupt requests (IRQs) on the system. • Ensure that enough RAM is available to support the device and driver. • Ensure that a direct memory access (DMA) channel is available if required. • Identify potential conflicts with other cards and devices. • Obtain the appropriate driver for the OS.

26. Installing a Non–Plug and Play Expansion Card • Read the expansion card documentation and note special requirements. • Check the computer configuration to determine available I/O addresses and IRQs. • Configure jumpers or switches on the card if required. • Turn off the computer and unplug the power cord.

27. Installing a Non–Plug and Play Expansion Card (Cont.) • Follow the appropriate ESD safety precautions. • Remove the cover from the computer. • Install the card in a free slot and power up the computer. • Replace the cover. • Power up the computer. • Install any software drivers or applications.

28. Installing a Plug and Play Expansion Card • Plug and Play allows for changes to computer configuration with minimal intervention. • Plug and Play devices allow the system to configure the card. • To allow Plug and Play devices to work immediately, the computer hardware, OS, and card must all be Plug and Play compliant. • Some systems require enabling Plug and Play in the system BIOS.

29. Considerations for Installing Hard Disk Drives • Ensure that the drive fits. If not, use a SCSI, USB, or parallel port interface drive. • Ensure that the system BIOS supports the size of the new drive. • Ensure that the drive controller supports the new drive. • Ensure that you have enough cables to install the drive.

30. Preparing to Install an Integrated Device Electronics (IDE) Drive • Hardware preparation consists of ensuring that • You have the correct drive • The drive fits into the computer • You have the proper cables to connect the drive • Software preparation consists of having a floppy boot disk with the format and fdisk utilities.

31. Installing an IDE Drive • Collect all necessary documentation for the drive and computer. • Back up any data you want to keep. • Turn off the computer and unplug the power cord. • Follow the appropriate ESD precautions. • Open the computer case.

32. Installing an IDE Drive (Cont.) • Check the documentation and set the jumpers for the drive, if required. • Connect the cable to the drives.

33. Installing an IDE Drive (Cont.) • Connect the power connection cable. • Install the drive in its bay. • Reconnect the computer power and boot up the system. Run the CMOS setup program if necessary.

34. Additional IDE Drive Installation Considerations • Set up and test a drive before final installation in the bay. • Avoid ESD and protect the drive from overheating. • Use disk management software in older systems that require it.

35. Additional Steps After the Physical Installation • Boot the computer from the bootable floppy disk, and run fdisk to create and set the partitions. • Format the drive. If it is the only drive, format it with system files. • Replace the cover on the computer.

36. Operating System Driver Installation • Device driver setup is no longer a complex task. • Microsoft Windows 98, Microsoft Windows Me, and Microsoft Windows 2000 have reduced the need for manual intervention. • Windows recognizes and configures Plug and Play devices automatically. • A wizard installs the appropriate drivers and resolves any device issues.

37. Using the Add/Remove Hardware Wizard

38. Motherboard Installation Considerations • Replacing the motherboard may be the most inexpensive way to completely overhaul a computer. • Some motherboards are proprietary and can be replaced only with one made by the same manufacturer. • The motherboard must fit into the existing case. • The motherboard must have the same built-in COM and LPT ports as the old one. • You should determine if the new motherboard has a built-in video card.

39. Motherboard Installation Considerations (Cont.) • The new motherboard must accommodate the existing expansion cards. • The power supply connector should be as close to the power supply as possible. • The existing drives must work with controllers on the new motherboard. • The memory on the old motherboard must work with the new one. • The upgrade should meet your current and future requirements.

40. Replacing a Motherboard • Replacing a motherboard is similar to building a computer. • The procedure is as follows: • Complete an installation checklist. • Follow the steps for disassembling a computer. • Check the settings on the new motherboard.

41. Replacing a Motherboard (Cont.) • Install the new motherboard. • Reconnect the case switches. • Follow the steps for computer reassembly (outlined in Slide 9). • Test the computer to ensure that it boots. • Complete the final testing and close the case.

42. Chapter Summary • Preparation is key to a successful upgrade or repair. Document everything. • Have a complete toolkit and take safety and ESD precautions. • Memory is probably the simplest upgrade performed by a technician. • Installing a new CPU and installing an expansion card are common ways to upgrade older computers. • Installing a new drive is not difficult when you follow the procedure carefully. • Installing a new motherboard completely overhauls the computer.