I had this exact problem for two weeks with my kt-7raid. Happened in either win2k or win98se. I'd get a crash every now and then, usually in a Vxd. Problem turned out to be ram that the system didn't quite like, though it worked fine in a 440bx board. Replaced it with some new pc133 ram, and it hasn't crashed or rebooted itself in close to a week now.