Video Performance: SD and HD
Finally, we set out to stress the new GeForce 8800 GT's PureVideo HD video processing engine, in terms of both image quality and CPU utilization with our HQV and H.264 playback tests.
HQV is comprised of a sampling of SD video clips and test patterns that have been specifically designed to evaluate a variety of interlaced video signal processing tasks, including decoding, de-interlacing, motion correction, noise reduction, film cadence detection, and detail enhancement. As each clip is played, the viewer is required to "score" the image based on a predetermined set of criteria. The numbers listed below are the sum of the scores for each section. We played the HQV DVD using the latest version of Cyberlink's PowerDVD, with hardware acceleration for AMD AVIVO HD and NVIDIA PureVideo HD extensions enabled.
Both ATI's and NVIDIA's current generation GPUs have no trouble with SD video playback. Both the Radeon HD 3870 and GeForce 8800 GT put up near perfect scores in the HQV test. In case you're not familiar with HQV, 130 points is the maximum score attainable. At 128 points, a PC equipped with either of these graphics cards plays back DVD video at quality levels better than the vast majority of set-top DVD players on the market.
Next we conducted quick a test using an H.264 encoded movie trailer clip for "Beowulf" which is available for download on Apple's QuickTime website. The CPU utilization data gathered during these tests was taken from Windows Vista's built-in Performance Monitor. The graphs show the CPU utilization for a GeForce 8800 GT and a Radeon HD 3870 using PowerDVD to playback the QuickTime clip.
GeForce 8800 GT
Radeon HD 3870
With a powerful quad-core processor at the heart of our test system and an unencrypted HD video clip being played, both the GeForce 8800 GT and Radeon HD 3870 averaged low, single-digit CPU utilization in this test. We should note that with hardware acceleration disabled, playing this video clip results in about 12% - 15% CPU utilization, so there is a marked improvement with both PureVideo HD and AVIVO HD.