I'm new to the forums, but have been a reader for some time. I'm not sure if this is the correct location to post this, but please to flame me too much.
I currently have a homebuilt PC which is about ~3yrs old. It has been upgraded several times, but has never gave me trouble. Within the last day and a half, it has started turning off completely on me, without warning. This happened twice. Then, it now is deciding to simply restart on me, which has happened a few more times. I assume it's related to heat, although the case is cooled well, and has good ventilation (imo).
When running GPUz, I see my video card running ~70 Celsius, in my BIOS my "cpu" is showing ~37 Celsius. My cousin recently had a similar issue, but he was told his issue was the North Bridge overheating.
I have been currently on the PC for about ~30mins with no problems. It would seem I'm running into the issue while playing Modern Warfare 2 or World of Warcraft, possibly other games as well, which again made me think about overheating via Video Card.
Any one have an idea? This sounds fairly common, and I only did some brief research. I consider myself knowledgeable when it comes to PC's as I have built 3-4, worked in PC retail for 4+ yrs, etc. I'm coming here for a wider variety of knowledge.
My PC spec's are as follows (assuming it doesn't show in my signature):
AMD Phenom II X4 940 BE
Gigabyte MA790X-UD4P MOBO
4GB DDR2 400mhz Corsair RAM
Zotac nVidia 8800GT Video Card
Creative XFi Extreme Sound Card
x1 WD 160GB HDD
x1 WD 1TB HDD
Windows 7 Ultimate
Currently have 5 Case fans - two exhaust, two intake, one side. Plus CPU and GPU fans as well. Both of which are stock.
Are those GPU temps when idle or during heavy load? If the GPU reaches those temps when doing nothing it could possibly be overheating. If so you know the drill, check the fan/heatsink and apply new thermal paste. Also check if the fan is working, and manipulate them to 100% when gaming.
You can run stress tests on your system like OCCT and see what happens, also try the PC on safe-mode for some hours.
That could also be a driver issue, or a bad RAM failure. Frankly, it could be anything, maybe your PSU is dying if it's too old, or it ain't pumping enough amps to keep the system up.
I'm not really sure, I've seen so many similar posts here and I too have been suffering from a similar issue for a year.