Build Your Own PC --Page 2

Screws, Spacers & Jumpers
Typical case screws are used to screw on the
case covers and anchor plug-in cards to the case

 

A drive screw's thread is finer and thinner than screws
used for the case. This kind of screw is generally used
to affix the drives in the drive bays, and
to screw the motherboard to the case

Spacers are screwed into the back plate for the motherboard
*Installing extra spacers not screwed to Motherboard could damage board.


A jumper is nothing more than a metal bridge that connects two contacts. We don't see the metal, though, because it's covered with plastic. Jumpers are often used to configure the PC. For instance, you can use them to set the processor speed or change a drive from a "master" to a "slave." Pictured above is a classic jumper, as used on drives and boards.

Motherboards

 

The image shows a typical motherboard. At the top on the left hand side are the interfaces and connectors (I/O ports) that stick out of the case at the back of an assembled computer. The expansion slots are below. The video card slot is used exclusively for the graphics card. The PCI slots will hold network cards, sound or video-editing boards. At the bottom right are the panel connectors for the on/ off button, the hard drive LED, the reset switch, and the operating LED. Take time to familiarize yourself with where they're located. By the way, LEDs that don't light up can generally be fixed by simply turning the plug around. The two IDE and SATA connectors are in the middle, while the connector for the floppy drive (34-pin FDD connector) is top right side of the image.

Check to make sure it really aligns properly with the I/O connectors on the back panel of the motherboard. We've seen cases where an incorrect I/O shield is included in the package. If you install the shield, then try to force the motherboard to fit, you may end up with a broken I/O connector.

More common are unpunched cutouts which mate to an I/O port. Again, trying to force an I/O connector through an unpunched cutout could end badly. Make sure any cutouts that need to be punched out are, indeed, removed.

Onboard Components

Keyboard, mouse, two serial connectors, a parallel port and two USB ports are on the ATX port panel. Some motherboards, like the one here, feature optional sound and joystick jacks. There are also models that have a monitor connection. That saves a slot and some money, but you'll have to deactivate the onboard chip if you plan to replace these cheap onboard modules with a higher-quality expansion card. It's generally impossible to run both chips at the same time. Once again, it can either be done in BIOS or with a jumper. Check your handbook to find out which method to use.

Basic Motherboard Configuration

Many modern motherboards with integrated software configuration no longer require you to do anything prior to assembly. That means that you type your processor parameters directly in BIOS (Basic Input Output System). Most of the time, you access the BIOS menu by pressing the DEL key, F2 or F10, shortly after switching on the PC. Check your handbook to find out which key to use. The latest technology even recognizes the CPU automatically, a feature that is particularly useful for beginners. But making settings manually is still a must for anyone who wants to fine-tune his or her system.

Motherboard Connectors
  • Several cables and plugs from the inside of the case must be connected to the motherboard. These cables and plugs are usually connected manually and one-by-one to connectors on the motherboard. You need to pay attention to any connection orientation for the cables and plugs. If any, notice the position of the first pins of the connectors on the motherboard, which are often marked.
  • The actual position and marking of the connectors on the motherboard vary greatly from brand to brand and from model to model. Read your motherboard manual carefully before any installation. Here is a list of most frequently used connections and their purposes:
    • System speaker (often 4-pin plug), for system sound
    • Hardware reset connector (often 2 pin plug), for resetting/rebooting the computer
    • Keylock and power LED connector (4 or 5-pin plug), for indicating computer on and off
    • HDD LED connector (often 2-pin plug), for indicating the usage of hard disc drives
    • Power connectors for case or microprocessor fan, supplying DC power to fans
    • Power switch (often 2-pin plug), for turning the computer on and off
    • DC power input connector (One 20-pin plug for ATX for 3.3V, +5, -5, +12, and -12V DC voltages; two 6-pin plugs for AT for +5, -5, +12 and -12V DC voltages), supplying DC power to the motherboard
    • For ATX motherboards, serial and parallel ports are built-in on the motherboard. For AT motherboards, you must also connect these ports to the corresponding connectors on the motherboards. Watch for the polarity of the plugs for the ports. Align the colored edge of the ribbon cables to Pin 1 on the connectors.
    • For ATX motherboards, PS2 mouse connectors are integrated into the motherboard. For AT motherboards you must attach a serial mouse to one of the serial port. Or you may have a PS2 mouse connector on the motherboard to use a PS2 mouse on an AT motherboard.
    • Some ATX motherboards come with ATX form factor connectors (8 pins)
    • Motherboards with integrated audio and/or video will come with special cables and plugs for these onboard devices. Consult your motherboard manual for details.

 

Build Your Own PC Page 3