Skip to main content

Curbing Your GPU's Power Use: Is It Worthwhile?

Benchmark Results: Cinebench R11 And PowerDirector 9

Desktop Usage: Cinebench R11

Based on our results, you will not notice any difference in performance between the tested settings. Even at lower clocks, the Radeon HD 5870 still ends up faster than the HD 5770. This just goes to show that, for most desktop applications, you only need a mainstream graphics card like the Radeon HD 5770. The other thing we’d like to point out is that the Radeon HD 5870, operating at lower clocks, is only slightly slower, at least in desktop applications. Now, let's look at the power savings.

We're including average power consumption numbers, in addition to peak power consumption, for the entire test. Running at DXVA clocks, the Radeon HD 5870’s peak power consumption is actually lower than the Radeon HD 5770. The Radeon HD 5770 still proves to be more frugal in average power measurements, thanks to its less complex graphics processor. With lower operating voltages, the Radeon HD 5870 winds up with lower numbers. Even more impressive, the difference is a mere three watts higher than a Radeon HD 5670.

H.264 GPU-Accelerated Encoding And Filters: PowerDirector 8

With hardware-accelerated decoding enabled, these graphics cards run at their respective UVD clocks. For reference, we've also included results without hardware-acceleration with the card running at its maximum clock settings (875/1250 MHz). Hardware-accelerated decoding is enabled at both undervolted settings.

For those interested, we've also included peak and average power consumption numbers here, in addition to total power consumed during the test. The changes we made to the Radeon HD 5870’s BIOS allow it to consume less power than the Radeon HD 5770. This is even more impressive when we consider the fact that the Radeon HD 5770 is also running at UVD clocks (400/900 MHz @ 0.95 V), rather than its maximum clock (850/1200 MHz @ 1.2 V). With the changes, the tweaked Radeon HD 5870 is not that far from the HD 5670, also running at UVD clocks (550/900 MHz @ 1.0 V).