Video Acceleration Tests
As in our test of the GeForce 6800 Ultra we tested the two new X800 cards to see how well they accelerated the playback of various video formats. The test procedure remains unchanged from the previous test. We tested the CPU load while playing back a file in VCD format (MPEG-2), a DIVX encoded file and a 1080p HDTV clip in WMV9 format.
Although NVIDIA has sent us a new beta driver since the launch of its GeForce 6800 Ultra, this new version did nothing to remedy this card's bad performance when playing back the HDTV and DIVX clips.
Here we tested the CPU usage while playing back VCD MPEG videos. All cards lower the CPU load to nearly nil.
During DIVX playback, almost all cards aside from the GeForce 6800 Ultra are practically equally fast. The 6800 Ultra leaves a good deal more decoding work to the CPU, however.
While the FX5950, 9800XT and the new X800 boards are once again neck and neck, the GeForce 6800 is clearly the "laziest" by far, letting the CPU do the work.
As we can see, the new X800 cards are neither faster nor slower than the Radeon 9800XT. Although, according to ATi, the video decoding functions are carried out by the pixel shaders of the GPU, the greater number of pipelines in the X800 does not seem to improve performance or lower the CPU load in any way.
