|Sapphire ATI Radeon HD 5850 Video Card 21162-00-50R|
|Reviews - Featured Reviews: Video Cards|
|Written by Olin Coles|
|Thursday, 15 October 2009|
Page 13 of 16
Radeon HD 5850 Temperatures
Benchmark tests are always nice, so long as you care about comparing one product to another. But when you're an overclocker, or merely a hardware enthusiast who likes to tweak things on occasion, there's no substitute for good information. Benchmark Reviews has a very popular guide written on Overclocking the NVIDIA GeForce Video Card, which gives detailed instruction on how to tweak a GeForce graphics card for better performance. Of course, not every video card has the head room. Some products run so hot that they can't suffer any higher temperatures than they already do. This is why we measure the operating temperature of the video card products we test.
FurMark does do two things extremely well: drive the thermal output of any graphics processor higher than any other application of video game, and it does so with consistency every time. While I have proved that FurMark is not a true benchmark tool for comparing video cards, it would still work very well to compare one product against itself at different stages. FurMark would be very useful for comparing the same GPU against itself using different drivers or clock speeds, of testing the stability of a GPU as it raises the temperatures higher than any program. But in the end, it's a rather limited tool.
To begin my testing, I use GPU-Z to measure the temperature at idle as reported by the GPU. Next I use FurMark 1.7.0 to generate maximum thermal load and record GPU temperatures at high-power 3D mode. The ambient room temperature remained at a stable 20.0°C throughout testing, while the inner-case temperature hovered around 36°C. The Sapphire ATI Radeon HD 5850 DirectX 11 video card 21162-00-50R recorded a cool 38°C in idle 2D mode, and increased to only 72°C in full 3D mode. These temperatures were much lower than the reference-design HD4890 at idle, indicating that reduced heat is a direct result of lower idle power draw.
The Cypress GPU has a massive 334 mm2 die size, which offers a much larger footprint for cooling the 2.154 billion transistors when they're just sitting idle. So with this in mind, it's understandable to see an impressive low idle temperature (although it's slightly highter than the Radeon HD 5870's idle temp). The reduced clock speed lends itself to a reduced maximum loaded temperature, making clear that the ATI Cypress GPU has thermal and power management under close control.