I'm having similar problems. Anything at 1600 FSB just causes problems. I can run 9 X 1800 and boot, P95 24 stable, but If I run a game, and try to tab over and use my web browser, the system just restarts itself. I'm running a memtest right now and It looks pretty good so far. I cant find what is causing the random restarts. I've tried backing down the multiplier, same result. Anyone know of possible causes for random restarts? If I can get rid of this bug I'll be completely stable.