I just put together a new build, and my EVGA 780i SLI will just randomly restart whenever it wants.
EVGA 780i SLO
E8500 OC to 4.5Ghz PRIME STABLE FOR 2 HOURS
OCZ Reaper 1066 4 gig CAN'T GET RAM TO RUN AT 1066 NO MATTER WHAT I DO
850TX watt Corsair Single Rail PSU
EVGA GTX 260 - 216 Superclocked in SLI
The cpu is prime stable for 2 hours, so i'm 100% sure its not that, because it restarts even while just browsing the web.
I can't get the ram stable at 1066 no matter what i do. I've tried everything, so I have it a 950Mhz
Sometimes it'll run fine for hours, other times 10 mintues. It's very intermittent.
Do you think I have a bad board? Could it be the ram?
I had a 680i that ran fine for 2 years then it started doing everything you described. I could run Orthos with no problems, game with no problems, pass memtest with no problems. Then out of no where it would just crash, was driving me nuts. Sent the board to ASUS, they sent it back the same way. Sent it back again, they sent it back the same way. Finally it made it to 3rd level support and they found a short in the mem slots, it was the board. I would test with another PSU if you have one to rule that out before RMAing the board.
HundredIslandBoy is in the right area, I dont think you are stable. 2 hours is not enough. How are you stressing the cpu? Try running linux passes atleat 15, I bet it wont do it. I think your memory configuration is set wrong or too high. Stress on stock or overclock speeds using prime 95 with emphasis on memory! keep an eye on the temps during testing.