Main components of a motherboard.

The image shows an ASUS motherboard. At the top on the right-hand side are the interfaces and connectors that stick out of the case at the back of an assembled computer. This board is designed for AMD Athlon and Duron processors. Socket A, as it's called, is labeled "CPU socket" in the picture. The expansion slots are to its left. The AGP slot is used exclusively for the graphics card. The PCI slots will hold network cards, ISDN, sound or video-editing boards. At the bottom left 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 connectors (40-pin) are below in the middle, while the connector for the floppy drive (34-pin FDD connector) is in the left side of the image. We'll describe the cables and drive configurations on the next page.

Onboard Components

ATX connector panel

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.