You've got a hardware problem.

I administer a network of 50+ PCs running, mainly, XP also a few running 2000 and 2 running 98. If I had to reinstall and reformat as many times as the PC quacks and MAC evangelists would have you believe then my job would be impossible.

I have no idea what your problem is but; if it's a new machine, complain to your hardware supplier, otherwise post some system specs and OS versions. Nobody can help you with the information you've supplied.