HDD: WD Blue 1 TB Desktop Hard Drive: 3.5 Inch, 7200 RPM, SATA 6 Gb/s, 64 MB Cache,
Mobo: ASUS SABERTOOTH 990FX R2.0 AM3+ AMD 990FX SATA 6Gb/s USB 3.0 (Bios 1708)
CD Drive: ATAPI iHAS124 Y SATA
Let me say that everything is fairly new except my PSU and Cd drive which are about 4-5 years old. I've updated my drivers for my video cards even tried beta drivers to no success. The problem mostly occurs in game that have a high demand of graphics. Lets use Metro 2033 as an example, I will play the game for on average 10-20mins and computer will freeze on the screen than few seconds later to go a black screen. I've tried swapping Video cards slots on the PCI. I've tried rebooting windows and reinstalling drivers. I've done stress test on the video card and have gone to 70Celsius and were stable for 20-30mins with no issues. When I play in game temps average 60-65 celcius on a hot day. I've updated the bios on the motherboard. I did buy the Video cards 4 months apart. Previous video card worked flawlessly. I did buy the second card used only due to the fact it was the only one left but I have warranty and I was assured the card was tested and fully working.
I'm sure their is more but I can't think of it all off the top of my head.
If I've missed important information please feel free to ask, this is my first time getting tech support over the internet. Go easy on me.
most likely a psu problem, probably has bad capacitors if its 5 years old. I read a review about that psu and the capacitors weren't good quality ones anyway. you only need about a 700w psu for that setup if its a good quality one. It would be good if you had another psu to test this. If you want, unplug and remove the psu and open up the cover and look for bulging or leaking capacitors, don't touch anything as they hold a lot of voltage even when unplugged.