|Sapphire Radeon HD 4890 RV790 Video Card|
|Reviews - Featured Reviews: Video Cards|
|Written by Olin Coles|
|Friday, 03 April 2009|
Page 12 of 15
Radeon HD 4890 Temperatures
This section is probably the most popular for me, not so much as a reviewer but more for my enthusiast side. 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.
To begin my testing, I use GPU-Z to measure the temperature at idle as reported by the GPU. Next I use FurMark 1.6.0 to generate maximum thermal load and record GPU temperatures at high-power 3D mode. The ambient room temperature remains stable at 18.0°C throughout testing, while the inner-case temperature hovered around 32°C. The ATI Radeon HD 4890 video card recorded 57°C in idle 2D mode, and increased to 84°C in full 3D mode.
FurMark is an OpenGL benchmark that heavily stresses and overheats the graphics card with fur rendering. The benchmark offers several options allowing the user to tweak the rendering: fullscreen / windowed mode, MSAA selection, window size, duration. The benchmark also includes a GPU Burner mode (stability test). FurMark requires an OpenGL 2.0 compliant graphics card with lot of GPU power! As a oZone3D.net partner, Benchmark Reviews offers a free download of FurMark to our visitors.
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.
Considering the results, I will admit that 84°C is not the kind of temperature expected from the RV790 GPU. Even with a slightly-larger contact footprint from the new 959-million transistor GPU matched to a double-height cooler, the temperatures at idle and load are practically identical to an overclocked Radeon HD 4870 under full load. For gamers who like to keep it cool, the surprisingly silent fan under load can be dialed up using free tools such as RivaTuner.
The most favored feature of past upper-level GeForce designs has been the focused exhaust design. Heated air recirculating around inside the computer case is could reduce stability for your sensitively overclocked computer system. While 84°C is considerably hot under maximum load, it's almost twenty degrees cooler than a reference-design Radeon HD 4870. This is what sets the RV790 apart from the RV770: three-million more transistors to improve chip stability, efficiency, and yield lower idle temperatures. In the end, this makes the ATI Radeon HD 4890 a more flexible graphics solution for multiple SKUs among card partners.