A very important feature of both GTX 780 and GTX 770 is improved cooling and new thermal control. The new Boost 2.0 algorithm will reduce the GPU clock if the temperature goes over 80 degrees.
Nvidia’s reference cooler for the GTX 780 and GTX 770 was borrowed from the GTX Titan and it perfectly fits the cooling requirements of the Boost 2.0 algorithm. The ACX cooler is quiet, even under load. It’s not inaudible, of course, but it won’t be a distraction during a gaming session. The card is completely silent in idle.
The EVGA ACX cooler is superior to the reference design as it keeps the GPU temperatures below 70 degrees, which is 10 degrees or 14 percent better than the reference unit. If the ACX cooler wasn’t as good, GPU Boost 2.0 would kick in and throttle the card once it gets too hot for comfort.
During our Unigine Heaven test at 1080p, with extreme tessellation settings, the GPU hit 64 degrees Celsius. In the same test a reference GTX 770 hits 79 degrees. In Crysis 3, at 2560x1600 and very high details, the GTX 770 SC ACX heats up to 69 degrees, while the reference card hits 79 degrees.