This will let you set your own custom profiles, clock speed, memory speed etc. If you are unstable, you may not have enough voltage across your GPU for the higher clock speeds. You can use Afterburner to unlock your voltage control as well but be VERY CAREFUL. Increasing your voltage too high can damage your card.
1: Increase clock speed
2: Test stability
I)Within your thermal comfort zone? Go To step 1
II) Too Hot? Decrease voltage? Go To step 2
I) Within your thermal comfort zone? Incrementally increase voltage, back to step 2
II) Too Hot? Decrease clock speed.
Continue until you reach the point where you can't stay stable without overheating.
There is a lot of variance from chip to chip. I can't tell you an exact voltage for a specific clock speed. But if you follow the steps, you'll find it for yourself.
I suggest FurMark for stability testing (google furmark for the download)
You can run it in windowed mode with GPUZ open next to it to watch your temps. It will seriously work your card.
Idle temps can be anywhere from 30-40C and load temps can be anywhere from 70-90C
Furmark heats your GPU like nothing else. For my personal overclock I get to the mid 80s in Furmark and games only get to the High 60s sometimes low 70s.
So, if you Get up to 90C in Furmark, your normal operating temps shouldn't be out of control. I would not recommend 90C for normal everyday use, but during a stress test, it would be acceptable (for me personally)
Sounds like you have a pretty good overclock. You got to 900Mhz which is a pretty good overclock. You could try for 950, but your temps might start to get out of control. I like to make sure my GPU is stable under an extreme stress test to make sure it will be stable no matter what games I'm playing. You could probably go a little higher because your game temps are low, but be careful. You don't want to wreck your card.
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