If your in xp, its a known bug. Shammy said something about messing with turbo performance settings to get rid of it but I've yet to find the sauce. Win 7 and Vista don't have this on shutdown or restart sequences.

Thanks for the info. I'm guessing I need to play with that nifty little turbo feature I was asking about earlier?

The good news is that the BIOS seems to have just a touch more efficiency than the old one I was on. Now I just need to test super pi to confirm.