What mobo you do you have?
as far as i know, i don't have one....
LOL...that's farkin' funny...
Dude, the motherboard is the big circuitboard that everything else (CPU, HDD,etc.) plugs into (I'd like to see how your PC works without one...
).
Download Sandra (from link in Dukat's post), it'll tell you everything you need to know about it.
You could also open the PC and look for a brand/model number on the board itself (should be fairly easy to find), and then Google it.