I posted this problem a while ago and said I'd "fixed" it be getting rid of the sound card, but I was wrong - the sound card made the crashes more obnoxious, but it wasn't the cause - I crashed consistently after I got rid of the soundcard and again after I got the replacement from Creative. The gist of the problem is: My machine will freeze OR BSOD OR reboot randomly if left idle for a long time. I never crash as long as I am doing intensive things with the computer - playing system-hog games, 3d modeling software, 3dmark05, etc.. Some weekends I have played many hours of games and everything is fine; leave it idle for an hour and I come back to either a rebooted or frozen machine. Even surfing the web now I am liable to crash. But start up Civilization 4 and go to work and the machine will still be functioning fine when I get back. Asus a8n-sli premium mobo AMD athlon64 x2 4400+ 2x 1gig sticks of OCZ ram. Creative X-Fi Nvidia 7800gt 250 gig SATA Western Digital drive. Windows XP pro - all updates are the latest (SP2, etc.) ASUS probe returns no funny voltage drops before it goes down. Memtest reports no errors (also, it still crashes if I run with only 1 stick of RAM, and I tried both by themselves). chkdsk /r /f found no errors. 7 Minidumps attached. Any idea what Windows is doing when it is idle or otherwise unbusy that could tickle my machine into crashing? Thanks very much for your help! This is driving me nuts.