Original Equipment Manufacture
It is usually just the main piece of equipment without the CD's, manuals, connection wires, etc.
Sometimes it's good depending on your situation. Almost all Hard drives are OEM. If you plan on doing overclocking on a processor, OEM ones are good, because you're buying an aftermarket heatsink anyway.
I always buy retail motherboards and video cards though....
<b>I'm an unhyphenated American.</b>
Intel Q6600 @ 3200 1.4v
Abit IP35 Pro "The Snake"
2x2gb A-Data @ 800
Diamond HD 3870 512mb
Great FORD TRUCK