I have a comp that's been playing up now for over 2 months and there is nothing predictable to what its going to do, when I boot it post every time with no problem, but then it may reboot before getting to windows 1st load screen, maybe several times, it can get to windows sometimes then reboots before the desktop finishes loading, sometimes it can get windows loaded and sit there without using it and all's fine, then I go to load a web page and then it reboots again. Sometimes after all this rebooting it may decide to work with no problem for a few hours till I shut down normally.

Rarely a blue screen will appear with a stop error with a different code most times. Most times there is no blue screen.
When selecting "Disable automatic restart on system failure" it still reboots with no BSOD.
Tried getting to safe mode a few times, works sometimes, other times it reboots as the screen with the drivers are loading. Twice now after crashing on the safe mode driver screen an error has occurred where it says the registry file is missing or corrupt, then the only way to get it going again is boot to windows cd and repair.

The power supply blew up with a bang about 4 months ago but had been working fine with the new one installed,
I have tried 4 different sticks of ram, one at a time, in different slots,
Tried different video card,
Tried different HD with fresh format and windows installed, still rebooting. Different sata cable,
Checked all cable plugs,
Checked temps with "Open Hardware Monitor" for awhile, all temps were fine,

Any ideas what else I can try?? Is this a motherboard or CPU dying??


Gigabyte GA-N650SLI-DS4L
Intel Core2 Quad Q6600 2.4GHz
Windows Vista