I have disabled computer restart and still no BSOD screen. I checked the Event Viewer and no errors at time of restart.
It seems to only happen at 1680X1050 resolution (max)
Its not an overheating issue. Furmark doesnt crash it and neither does Prime95. I have reinstalled drivers using driver cleaners too. One of the games I play seems to not crash at all on 1280X960. This computer has ran fine for 2 years up until about 3 months ago. Power issue is what I am thinking now, but what would create a sudden power issue?
Currently all on default Bios settings.
4gig Gskill 1066
Thermal Take tough 650watt modular
Make sure you clean your GTX 280 to ensure good cooling. I have a BFG GTX 280 OC and the card is hot. I regularly clean it with GAS-CAN to minimize dust build up. My card is ~ 2 years or probably older but it runs like a charm.
Also try an older driver version that you know it works for you. Run Ntune to fine tune your setup.
Be sure to use that canned air to blow out that power supply too. If its overheating with dust bunnies partying in there it could do the same thing. A good overall system cleaning would be the first start. If that doesn't work then I would consider the power supply as a problem too. If you can borrow one from somone as jsc suggested that would be the cheapest alternate route, otherwise you could buy a 20.00 tester with the voltage readings or just pick up a power supply from a local supply store such as microcenter or frys electronics.
Personally when I have issues arise like that, I like to take my system completely apart, clean it out like new, reassemble everything and go from there to make sure everything is seated well and not overheating before I buy any new parts but thats me. I'm a freak like that...
Unless that's one of the new Thermaltakes, it is probably crapping out on you, and is no longer able to hold up its end of the log. Does it have a little voltage switch on it? If so, it's an old model, and should be replaced. Your symptoms are consistent with a power problem. Anything in the Windows Event Log? Driver or other software problems will often manifest there, but an outright shutdown is probably power.
If you need a new PSU, choose one with full range active PFC (no little voltage switch) and 80+ certification. A decent 500W-550W PSU like Antec, Corsair, Seasonic, or Enermax would be enough for you.
That one should be okay. Check to see if you've exceeded one of the +12V rail's OCP settings by switching which modular connectors you are using. Unfortunately, I downloaded the manual, and there was no indication of what rail powers what line, so this may or may not make a difference.
I am having constant but random restarts while playing PC games. My computer restarts even though I have automatic restarts turned off. I am getting no errors in the Event Viewer. All my temperatures are fine. CPU<40c GPU<75c and the case temps seem fine. I notice in one game (Asheron's Call), that when there are large spell animations covering a large area of the screen I get a restart, I can almost force a crash/restart at will. Starcraft 2 is restarting often, especially with Cloaked (special animation) units are on screen. I have never had a restart/crash during normal computing, only video games. I am down to GPU, PSU, and maybe Hard drive?
An issue that I just discovered is that I get a BSOD when attempting to start in Safe Mode.
I ran a checkdisk, defrag, uninstalled and reinstalled GPU drivers. I have ran PRIME95 and Furmark for short tests, no crash. I have ran Malwarebytes a couple times and no virii. I have Avast antivirus running and I cannot uninstall due to no Safe Mode.
Windows XP fully updated
Intel quad Q6600 default speeds Tuniq Tower cooler
Gskill 2x2gig ddr2 1066
Evga GTX280 default speeds
Seagate 7200rpm 250gig HDD SATA
Asus P5k Deluxe
Thermaltake toughpower 650w
Antec 900 case.
Pick up a cheap GPU somewhere and test. In Safe Mode, your GPU drivers aren't loading, so your GPU is probably running flat out instead of being allowed to idle. This sounds like a PSU problem; your Thermaltake is not able to hold up its end of the log.