Power, Temps, Noise and Overclocking
As with the Radeon 6900 series the 7700 series performs power management in a different way to older cards so we have changed the way we test power and temperature levels in our reviews. For idle power we list the full system use at the wall after sitting at the desktop with no activity for 5 minutes. Load power is the highest reading we saw for the full system when testing during this review. Temperatures are taken in the same way. Noise levels are taken after a period of prolonged gaming in a scenario which applied maximum load to the GPU.
This is the page which shows the most impressive "win" for the 7770 in this review as the power use of the card is significantly lower than the GTX 560. As well as that we also get a far better load temperature from the Sapphire card with the Vapor-X cooler working well. The most impressive aspect though is the noise level. Even at full load the 7770 Vapor-X is whisper quiet, it is almost like it is off when in use.
Sticking with the power and noise theme for a moment, as with our other articles on the 7000 series we also need to note that one of the key 7770 features is the advanced power management which has been implemented in Crossfire. In that mode AMD are able to send the second card to an ultra-low power state when idle and as shown below this means turning the GPU and memory to 0MHz.
As an added bonus to the second (or additional) cards minimal power use the driver also shuts down the fan turning the card into a silent model.
Moving to overclocking we get to take a look at Sapphires own tweaking utility, TriXX. TriXX is a free tool available from the Sapphire website which allows us to change the speed and fan settings on our card. It is a simple process and no more than moving a few sliders.
The Vapor-X is heavily overclocked at the factory so it comes as no surprise that there are only small gains to be had in this area. That said a core speed of 1195MHz and memory of 1335MHz is very impressive for a 7770 card.