Keyboard suddenly dies - anysuggestions

This one has got me stumped. I have tried 3 ps/2 keyboards and 1 usb keyboard.

Sometimes the keyboard will simply stop working on my work pc. It's a p4, 3 ghz, running on a 915 intel board ( i think). Running xp sp2.

About 6 times a work day the keyboard loses all functionality (usb mouse still works). Unplugging it and putting it back together solves the problem.

I can't think of whats causing this or how to solve it. As stated above I've used multiple keyboards with different interfaces. I've ran ad-aware, virus scan, etc.

I'm open to any suggestions.

no, and it happens all of a sudden. maybe not in a middle of typing a word but its definately not something like the computer not waking up. It just loses power. Thats why I thought switching to usb might work.

Anyway, it seems to be not happening as frequent after I put it on a piece of wood. Maybe it was static electicity from my metal desk. (I know, I know --- the platic on the bottom of the keyboard should act the same as the wood---- I'm just saying for now it is working)