Well, went to CompUSA (only thing open on sundays)and bought a new power supply this morning to give it a shot. (Before i left, i tried turning it on again after being unplugged all night, and got about 1/2 second of PS fan, followed by the light). I got home, installed the new power supply, ran just the cards, one stick of memory. It ran for about 10-15 seconds, then shut down. Same problem, unplugegd everything, tried it again. 5 secconds, then flashing light. Now, i'm leaning towards motherboard. The only thing i haven't done would be disconnecting all of the cards, and using the vid card/memory only. The other thing i found (i haven't really looked in my computer since i built it last year) was my CPU fan completely off, hanging by the wire with my heatsink dangling by one tab. Looks like somewhere along the line a tab broke, too. Of course, i don't think any processor damage could have occured because, as you said, everything' heat monitored. It would have shut it down in an instant if it overheated. Thanks a lot for your help.