Power, Temperature, And Noise Benchmarks
The performance numbers are interesting, but they only tell half of the story. Let's see how these cards compare when it comes to power usage, GPU temperature, and noise generation. First, power usage:
The GeForce GTX 480 is notorious for being power-hungry and the Zotac AMP! edition card is no exception, adding 30 W to the reference card's load numbers. Idle power usage is similar, however.
The factory-overclocked Radeon HD 5870 cards are showing a higher idle-power usage. The HIS card, in particular, which is unable to set clocks down to 157/300 MHz, is the biggest violator here. It compensates with load numbers closer to the reference card than Gigabyte's overclocked model. The Gigabyte Super Clocked model ups the load power ante by 30 W or so over the other Radeon contenders.
The Gigabyte cooling solution really shines in comparison to the other options when it comes to keeping GPU temperatures low. The Zotac AMP! edition card also makes good use of Zalman's VF3000 cooler to bring the GeForce GTX 480 temperatures to a reasonable level. Strangely, the iCooler V on the HIS card doesn't seem to be performing any better than the stock cooling solution, and actually delivers a the opposite effect, especially at idle.
We can see why the GeForce GTX 480 reference cooler has a bad reputation for being loud under load (although its idle noise is very acceptable). All of the other coolers do a similar job of keeping the noise down under load. The HIS iCooler V claims a lead in this respect.
