I took out a module of ram since I found errors in Mem Test on that single module and sent it in for RMA. Here are the troubleshooting options I took:
MemTest86+:6 passes, no errors.
Installed Windows 7, Installed newest drivers, Ran Prime95. Crashed.
After that test, I ran it into Safe mode, ran Prime95, perfectly fine. Passed.
That would mean it was some kind of software or drivers, so my next test.
Reformatted for Windows 7. Didn't install any drivers, ran Prime95, Crashed.
Redid it in safe mode, Prime95 for 8 hours, passed.
What would cause it to crash in Normal Startup but not in Safe Mode if it isn't the drivers or any software? On the clean install I didn't install anything and ran Prime95. It would crash in normal startup but not safe mode. It's puzzling me.
Crashes in Normal Startup, Passes in Safe before reinstall: Rules out hardware and may be Software or drivers.
Crashes in Normal Startup, Passes in Safe, after reinstall: Rules out software and drivers as it only contains the initial drivers and no 3rd party software.
What are your temps?? Typically, Prime95 crashes for either defective RAM or high temps. Since you ran MemTest86+ for 6 passes (7 is recommended), I would lean more to high temps. When you are running Prime95, report your temps using either HWMonitor or RealTemp and post back. My first thought is you didn't properly install your heat sink, so your temps are too high.
Also in SafeMode, you are running the minimum system requirements, so temps might not reflect true temps when running in normal mode.
My core temps are approximately 50 degrees C under load while my GPUs are at 90 degrees. (30, 70 at idle) I'm pretty sure it's not the temperatures which was my thought at first too. There are times when it just freezes too.
Yes, I've tried it with just one GX2. It's quite puzzling.