The boost speed may not seem all that impressive but consider that it would go between the 1220 to 1233MHz range in just about every game with the card under the 110% power envelope. All told that is a +69MHz boost over the already impressive 1137MHz factory boost clock and 135MHz higher than the factory memory clock. Free performance at its finest. By boosting the fan speed to 100% the card never saw the high side of 59 °C in my testing. At 64 °C the stock cooling performance is good but it gets better as expected with increased fan speed. Now normally with fan speed comes noise, but not so with this implementation of the DCU II design. Much like its cousin the GTX 660Ti DCU II TOP, I was able to close up the chassis and eliminate the noise form the card with the cooling solution for the CPU being the loudest thing in the case.



Link: OCC