Graphics card heat vs artifacting vs voltage question.

So say
I overvolt my graphics card to 1.300, and at this point i'm getting artifacts at 75 degrees... then i go and....
I overvolt my graphisc card to 1.250, and at this point it doesn't artifact, even when i lower the fan speed and the temp goes above 75 degrees, its not artifacting at 78 degrees...

Does this mean my card just cant take the extra voltage? and that it doesn't have anything to do with heat?
What can I do to allow my card to take more voltage at this point? Do I have to just live with the fact that one of my cards just can't go above 1.25 while my other the exact same card can do over 1.3 easy?

Are both cards clocked the same?

If one card can go above 1.3 and the other cant you cant do anything with it, Its like CPU's, If you're lucky you'll get a good quality silicon, You cant do anything with it.

There is a program (I dont know what its called) that can kind of check your silicon quality.
Edit : What i wrote above is valid only if both cards clocked the same.

blackjackel said:

Do I have to just live with the fact that one of my cards just can't go above 1.25 while my other the exact same card can do over 1.3 easy?

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Yes.
Luck of the draw.

M@rk said:

If one card can go above 1.3 and the other cant you cant do anything with it, Its like CPU's, If you're lucky you'll get a good quality silicon, You cant do anything with it.

There is a program (I dont know what its called) that can kind of check your silicon quality.
Edit : What i wrote above is valid only if both cards clocked the same.

Click to expand...

GPUz can show your ASIC score

myndlessdayz said:

GPUz can show your ASIC score

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Don't rely on ASIC, mine has 77.3% which supposedly makes her a good overclocker and i'm stuck at ~1470mhz, artifacts if i go above