Since video card temperatures and the heat generated by next-generation cards have become an area of concern among enthusiasts and gamers, we want to take a closer look at how the Radeon HD 5800 series does at idle and under a full load.
ATI Radeon HD 5850 Idle Temperature:
At idle the Radeon HD 5850 had an idle temperature of 38C, which is identical to the Radeon HD 5870’s observed idle of 38C. When we first looked at the Radeon HD 4870 in June 2008 we found that it had an idle temperature of 74C. As you can see from the screen shot above, the idle state of the Radeon HD 5850 drops the GPU frequency down to just 157 MHz and the memory down to 300 MHz to help conserve power and lower temperatures. The idle states appear to be the same between the two cards, so the slight temperature difference is likely due to one GPU being less ‘leaky’ than another. AMD has nailed idle temperatures on this series from the looks of it.
ATI Radeon HD 5850 Load Temperature:
We fired up FurMark and ran the stability at 1280×1024, which was enough to put the GPU at 100% load in order to get the highest load temperature possible. This application also charted the temperature results so you can see how the temperature rises and levels off, which is very nice. The ATI Radeon HD 5850 maxed out at 75C, but fluctuated between 73C-75C once it leveled out. The fan on the ATI Radeon HD 5850 video card was left on auto during temperature testing. The fan never got over 35% during testing, so manually increasing the fan speed in CATALYST Control Center would help lower the temperature some more if you don’t mind the extra noise. Our testing shows that the max load temperature on the Radeon HD 5850 was 10C cooler than that of the Radeon HD 5870!