GPU Stability stress testing

[Almin94]

Hello everyone,
I've been trying to OC my EVGA GTX 770 ACX, i believe I hit a stable OC at +60 (1200MHz boost clock) + 500 (2000MHz) at stock 1.2V.

The past few days I've been trying to push it a little further, for example +100 at 1.212V but I'm a bit confused with stress testing.
For example, with the +100MHz settings, it ran Furmark for 2 hours stable, temp about 72C, 3D mark, Crysis 3 at Ultra with 4xSMAA, Far Cry 3 max settings, Assassins Creed Black Flag also max and Metro LastLight (max without SSAA), but when I used Unigine Valley or Heaven, the program stopped working after a bit, and then displayed the same error again on every OC setting until I restart the system, so I considered it to be a software error.

So my questions are :
What program would you recommend to test my GPU stability?
How much time does the stress test need to run,for the OC to be considered stable?
Do different settings on the stress test (resolution, AA etc) have different impact, or does GPU core just needs to be at 100% load?
To test my memory clock stability, does the VRAM need to be at maximum load?

 

[huilun02]

Just loop 3dmark11 for an hour.

If you really want to put VRAM through the works, load up a game with HD textures and crank up the details/AA and maybe even use supersampling.

 

[RobCrezz]

Unigine valley on Extreme HD tests stability very well. Also Kombuster.

 

[danco5074]

I used unigine extreme HD and it was stable very high. I was very pleased but then noticed some artifacting while in a game, and I had to set the core clock down an extra 10MHz to get rid of it. So benchmark software is okay, but you will not really know until you test it out on gaming. Some games will be okay with it higher, others that are resource intensive will show artifacts. This is why there are multiple profiles.