That's 4 hours of running Windows and Folding@Home, and no problems. I'm going to try to overclock it a bit and see if it remains stable.
n7, I don't think it's RAM related, since my older, slower RAM exhibited the same problems repeatedly. I can believe it's the motherboard, but I am hesitant to call up Asus for a replacement without a smoking gun. Moving the video card doesn't seem like enough smoke.