Overclocking my GTX 680

[mimi93]

Hello I have a EVGA GTX 680 4GB. I am trying to overclock its memory using Precision X and have gotten it to +400 mem offset without any artifacts in OCX scanner. The problem is that after about 10 min of stress testing Precision X tells me that the card is running at 705MHZ instead of its (overclocked) 1280MHZ (+160 GPU Clock Offset). Why is the clock speed so much lower and how can I fix it? When I reboot everything is fine until I stress test it. Also I did not have this problem while attempting to overclock the GPU and using the stress test.

Other info:
mobo: asus sabertooth Z77

I know its not a heat issue since the card is watercooled and Precision X tells me my GPU temp is 35 degrees C while stress testing and I have let the card cool down an hour after I first noticed the above before I tried to stress test again.

 

[dragonsamus]

Use Heaven 3.0. If your overclock is stable all the way through then you're all set. If it glitches then the gpu will down clock to around 700 Mhz. It sounds like you overclock isn't stable. If your gpu does glitch while running Heaven 3.0, reboot your PC and lower the overclock by 5-10 Mhz and try to pass Heaven 3.0 again.

Make sure when using Heaven 3.0 that you have all settings on max.

 

[amuffin]

Don't OC the memory as much, aim for the core OC.

 

[Fireraga]

Don't OC the memory as much, aim for the core OC.

^->As he said, do not OC the memory, it yields no significant gain and brings with it the highest chance to break your gpu.

Stick to overclocking the Core shaders with the least amount of volts possible.

 

[mimi93]

Cool thanks. As far as I gather the EVGA GTX 680 is voltage locked, but then what does the power target slider do? How about the Adjust Voltage button on Precision X