Working Inside Your PC

If you've never opened up a computer before, it can be pretty overwhelming. In this section, I'm going to help you get started with practical advice on how to

• Open the case.

• Protect your system against electrostatic discharge (ESD).

• Connect internal and external data cables.

• Install a PCI card.

Some systems can transfer CD music through the standard ATA/IDE cable and don't require a separate patch cable. If you can play music CDs through your speakers and your system doesn't use analog or digital audio cables, don't worry about it. Most CD-ROM and other types of optical drives include analog or digital audio cables, but if you need replacements , most computer stores also stock them.

Opening the Case of a Desktop PC

I recommend that you look at your system manual for case-opening instructions, particularly if you have a retail-store system made by HP or Compaq. Depending upon the type of case you have, you might need to remove just one or two screws , or maybe a handful. If you're opening the case to gain access to the motherboard, you might need to do more than just take the cover off the system.

So-called "white box" systems are usually pretty straightforward to open, because they use case designs made for user access instead of low cost. Figure 2.18 shows the rear of two typical cases used by white-box computer dealers or as replacement cases. The computer on the left has a single screw holding the covers in place. After this screw is removed, the top panel must be removed before the side panels can be removed. The computer on the right uses four screws per side to hold the side panels in place, but the side panels can be removed without removing the top cover. The right-side panel can even be swung out and latched back into place for faster card and drive installation.

Figure 2.18. Two generic cases compared to each other.

Retail-store systems often use a single-piece molding that slips off the rear of the chassis. It can be held in place by several screws.

Taking ESD Precautions

After you open your PC, what should you do next ?

caution

Be sure to unplug the system before you open the case.

Don't mix up the screws used for the case with screws used for holding expansion cards or drives in place. Keep them separate. Label empty film or medicine containers and use one for each type of screw you remove.

Ideally, you should wear a commercial wrist strap made for ESD protection and clip it to an unpainted metal part on the computer you are servicing , as in Figure 2.19, before you touch any other part of the interior of your computer.

Figure 2.19. A wrist strap and some suitable places to clip it inside the system.

When you put the wrist strap on, make sure the metal plate on the inside of the strap touches bare skin; don't wear it over a shirt or sweater, and make sure it's comfortably snug. When the wrist strap is connected to a metal part of the chassis with the alligator clip on the end of the cable that snaps onto the wrist strap, it equalizes the electrical potential of your body and the computer to prevent ESD discharge.

However, if you don't have a wrist strap, touch unpainted metal on the chassis or the power supply before you touch or remove any cables or other parts . If possible, keep touching the chassis or power supply while you work.

For more details on ESD protection, see Chapter 13, "Safety and Recycling."

Connecting Internal and External Data Cables

Connecting internal and external drives and devices is critical if you want to have reliably working PCs. Here are a couple of examples of how to do it right:

Attaching Cables to the Floppy Drive and Controller

The floppy drive uses a 34-pin cable that has a twist at one end. This end of the cable connects to the floppy drive (A: drive). The middle connector is used for the B: drive (if present; not supported on some machines). The connector with the untwisted end plugs into the floppy controller on the motherboard. The colored marking on the cable and the twist indicate the pin 1 side of the cable. This is important to note because floppy drives and controllers are not always keyed to prevent incorrect installation.

The floppy drive is powered by a small 4-pin power cable. There is a small cut-out in the center of the connector on the drive that corresponds to a projection on the cable.

Figure 2.20 shows how the floppy drive cable and power cable connect to the rear of a typical floppy drive and to the floppy controller.

Figure 2.20. Connecting data and power cables to a typical 3.5-inch floppy drive (top) and floppy controller on motherboard (bottom).

To install the cables

1. Take the ESD precautions discussed in "Taking ESD Precautions," earlier in this chapter, after you open the case and before you touch the cables or other components .

2. Be sure to line up the keying on the cable (if any) with the cut-out on the floppy drive and controller connectors.

3. Push the cable firmly but gently into place.

4. Make sure the ridge on the power cable connector faces away from the drive; the power cable can be forced into place upside down, but this will destroy the drive when the power is turned on.

5. Push the power cable connector firmly but gently into place. If you don't have a spare 4-wire connector for the floppy drive, you can purchase an adapter, which converts the large Molex connector used for hard disks into a floppy drive power connector. You can also purchase a Y-splitter, which can power a floppy drive and a hard drive.

caution

If any pins are bent on the floppy drive, controller data, or power connectors, carefully straighten them with a pair of needlenose pliers before installing the cables.

The installation of an ATA/IDE hard disk or other drive type is similar in many ways, but the cables used are different and the drives must be correctly jumpered.

For more information on floppy drives and hard drives, cables, and floppy media, see Chapter 14.

Attaching the VGA Cable to a Video Card or Port

The VGA cable has as many as 15 wires that are routed into a connector the same size as a serial (COM) port. Consequently, it is one of the heaviest cables you need to connect to a PC. If you don't attach it correctly, you could have poor-quality images on your monitor, and if the cable falls off, you won't have any picture at all.

Depending upon the computer, the VGA port might be located on a card built into an expansion slot, or might be clustered with other ports at the rear of the computer. In either case, the port and the cable are the same.

Figure 2.21 shows how the VGA cable should be connected to the VGA port.

Figure 2.21. Connecting a VGA cable to a VGA port.

To connect the VGA cable to the VGA port

1. Turn the thumbscrews so they are completely retracted. If they are not completely retracted, they could prevent proper connection.

2. Check the VGA cable for bent pins, but don't panic if you see a few pins that appear to be missing. Most VGA monitors don't use all 15 pins. Carefully straighten any bent pins you find.

3. Line up the cable with the port and carefully push the cable into the port.

4. Fasten the thumbscrews tightly but evenly to hold the cable in place.

For more information about graphics cards and cables, including installing and configuring cards that support multiple displays, see Chapter 9, "Video."

Installing a PCI Card

Most systems have at least one open PCI card slot; it's the standard card type used for most devices. If you need to add an internal modem, a network adapter, a USB 2.0, an IEEE-1394a, a hard disk, or a SCSI host adapter to a desktop PC, you will add a PCI card that includes the necessary port.

Figure 2.22 shows the process of adding a PCI card ( specifically , a Serial ATA hard disk host adapter) to a typical system. The procedure for installing an AGP-based video card is similar, except that the AGP slot is used.

Figure 2.22. Installing a Serial ATA card into a PCI slot.

To add a PCI card

1. Shut down the system and unplug it.

2. Open the system.

3. Follow the ESD precautions discussed in "Taking ESD Precautions," earlier in this chapter.

4. Remove the slot cover behind the PCI slot you want to use.

5. Line up the connector on the bottom of the card with the slot.

6. Carefully push the card into place until it locks into place. Make sure the bracket on the card fits between the rear edge of the motherboard and the outer wall of the case.

7. Fasten the card into place using the screw you removed from the slot cover in step 4.

8. Attach any cables required between the card and other devices.

9. Double-check your work; then close up your system and follow the instructions provided with the card for driver installation and card configuration.

For more information about installing cards and configuring them, see Chapter 8, "Input/Output Devices and Cables"; Chapter 9, "Video"; Chapter 14, "Storage"; Chapter 19, "Installing and Configuring Hardware in Windows"; and Chapter 21, "Networking and Internet Connectivity."