It would have to be xp 64 bit, but I think I have figured the problem out. I removed the two 1 gig chips and I have now played wow for 2 hours no crashing!! whoowhoo, I even got it to play secondlife for an hour without crashing; which, has major known issues with vista at the moment. So I think im pretty well ready to go, the question at this point is if the chips or ram slots are bad or if there is just some funky issue with mixing the ram in this board.