I've been running this homebuilt rig for about 5 months now and I've spent that entire time trying to find the source of this semi-random freezing. It's just a sudden freeze with no warning, I've left the system on for hours to see if it would ever fix itself and it never has. What really gets me is that there doesn't seem to be any reason a particular game triggers it while another won't. for example:
Skyrim: Freezes very rarely, always on loading screens.
Vindictus: Fairly rare, always at the end of a mission after the boss is defeated
World of Tanks: I'm lucky if I can get through a match. It's common enough that I can use this to test whether the problem has been fixed.
Dolphin Gamecube/Wii Emulator: Freezes the instant the iso is loaded, without fail.
It has happened with nothing but Chrome and Skype running but that was maybe twice in the five months. I've also confirmed that these games will trigger it without these running.
Most games run fine, including: Borderlands, Portal 1 and 2, Battlefield 3, Torchlight 1 and 2, Planetside 2, Team Fortress 2, Minecraft...
Way too many to list. Point is most run fine but certain ones freeze with varying frequency.
And let me just emphasize: Battlefield 3 running on Ultra causes no issues, but freaking World of Tanks freezes every time. This is part of what's driving me insane.
Anyway, I've run diagnostics on the RAM and HDD, Swapped out the RAM with known working sticks, run without the GPU, monitored CPU temps (Never seen it above 50C, 40 is normal under load.), and run more than enough scans to be sure that it isn't malware. I've also tried more fixes than I can remember, including everything in this thread and several others that have long since been cleared from my history. So far, not even a clue.
My specs are:
O/S: Windows 7 Ultimate 64-bit
CPU: Intel Core i7-3820 Quad-core @3.6GHz(3.9 turbo)
Motherboard: Intel BOXDX79TO X79
RAM: G.SKILL Ripjaws X Series 8GB (2 x 4GB) DDR3 2133
PSU: PC Power & Cooling 750W
GPU: Radeon HD 6870
Display: ASUS 24" 2ms HDMI Widescreen
HDD: Seagate ST1000DM003 Barracuda 1TB Hard Drive - 7200RPM, 64MB, SATA 6Gb/s
Case: NZXT Phantom
Everything was brand new when the rig was built except the GPU, which is about 11 months old, and the PSU, which is several years old since I intentionally got a better one than I needed on my last rig so that I wouldn't need a new one.
I'm fresh out of ideas so anything's appreciated, thanks.
Okay, new info: The system has frozen with nothing but Youtube twice in the past couple of hours, which is highly unusual. The thing is, yesterday it froze while I was in the other room with a normally stable game paused. I've just realized that in all three instances, my router stopped broadcasting at the same time as the freeze and needed to be reset. Once is a coincidence, twice is a bit strange, thrice I would call correlation.