I have a MSI GTX 570 Twin Frozr III. I'd like to overclock the card but I dont know what are the maximum voltage and frequency limits.
another matter, if I increase frequency from 770 MHz to 850 MHz, what is the corresponding voltage value ?!
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Well most people would just play with the voltages and then check if its stable by running some benchmarks. There is concrete guide for overclocking.
I've overclocked my evga 570 to 850 MHz using 1026 mV but Azn Cracker is correct about just adjusting voltage till its stable. Best thing I've found is find a voltage your comfortable with and then adjust the clock frequency till you get it stable.