Noise, Overclocking, 2D Quality
Our GeForce 6800 GS being an engineering sample, its cooler could only work in two modes. The fan is rotating at its full speed and is rather loud until the OS and the ForceWare driver are loaded. After that the fan speed goes down and its noise diminishes, but not to vanish completely. The fact is the fan-control system on our sample of the card was programmed in such a way that the fan speed was constant in all the modes (2D, Low Power 3D and Performance 3D).
RivaTuner agrees with us: the sliders stand on 53% for all three modes. Of course, the speed-control system will be set up properly in the final revision of the card, and its acoustic characteristics will be like those of the GeForce 6800 GT which is not silent, but is not annoyingly loud, either. Moreover, some graphics card makers will surely equip their versions of the GeForce 6800 GS with quieter coolers.
We were much pleased with the overclockability of our sample of the card. We easily overclocked the GPU from the default 425MHz to 500MHz. The cooling system probably prevented it from speeding up more (the GPU was stable even at 540MHz, but there were some visual artifacts on the screen). But the real surprise was that the memory could work at 680 (1360) MHz – a fantastic achievement for 2.0ns memory chips! We know of many cases when Samsung’s K4J55323QF-GC20 could work at 550-600 (1100-1200) MHz, but not higher! Could NVIDIA have culled chips especially for the engineering sample of the GeForce 6800 GS or maybe they just increased the memory voltage? It is probable since we could not be mistaken. The monitoring module of RivaTuner reported the frequency gain, and this gain resulted in an appropriate performance gain in tests, and the card was absolutely stable at that.
You can rarely meet a graphics card today that would provide other than excellent image quality in 2D applications. The new product from NVIDIA was not an exception, giving out a crystal-sharp picture in all display modes supported by our monitors. We observed no fuzziness or ghosting or any other undesired effect. The next section of the review deals with the performance of the new graphics card in games.