sapphire radeon 7970

Solution
all card gpus are not created equally. some can take extremely high voltages, others with much lower voltages. there isn't a definative answer

Romeru

Honorable
Jan 11, 2013
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Like dude said.

You'll simply have to try by yourself.
Increase the core clock by 10-15mhz at a time and run a gpu stress test of some sort. if a driver crash occours increase the voltage by a small amount. and try again.