"By using either ASUS Smart Doctor or the commonly available Afterburner overclocking applications I was able to push the speeds up for additional performance. However, to get to the top clock speeds the voltage had to be tweaked some to reach the final clock speeds of 965MHz on the core and 1505MHz on the GDDR5 memory. Any higher than 965MHz on the core and stability was dependent on the game or test and could be pushed as high as 976MHz on the core, again depending on the game or test. Still even with that, 965MHz represents an almost 20% bump in core clock speed. The GDDR5 memory also yielded some big clock speed up to the overclocking gods with a 255MHz or just over a 20% increase over the default 1250MHz."
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