ATI Radeon HD 4670, Redefining The Mainstream
SD and HD Video Performance
We also did some quick testing of the new Radeon HD 4670's video processing engine, in terms of both image quality and CPU utilization with some standard and high-definition video playback tests.
Normally, we would use the HQV benchmark in this section of our video card evaluations, but the Radeon HD 4670 had severe issues with HQV with the pre-release driver we used for testing and scores produced by the card were meaningless. We have been in contact with AMD in regard to the issues and were told that they would be resolved in an upcoming driver release we expect to have in the next day or two. Once we have them, we will update this portion of the article with HQV scores.
In the meantime, because we saw issues with HQV, we decided to test DVD playback on the Radeon HD 4670 using a handful of store-bought, movies. Superman Returns, Eragon, and the Illusionist, save for some flickering during the FBI warning on the Superman Returns disc, all worked well on the Radeon HD 4670 with both PowerDVD 8 and WinDVD 8. Some DViX and MPG files we have in-house for reference also played back normally.
Next we conducted a test using an H.264 encoded movie trailer clip for "Beowulf" which is available for download on Apple's QuickTime HD 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 9500 GT and a Radeon HD 4670 using PowerDVD 8 Ultra to playback the QuickTime clip.
GeForce 9500 GT
Radeon HD 4670
With a fast quad-core processor powering our test system and an unencrypted HD video clip being played back, both of the cards we tested had low CPU utilization in this test. We should note that with hardware acceleration disabled, playing this video clip results in about 12% - 15% average CPU utilization, so there is a marked improvement with both PureVideo HD and UVD 2. Also note that with encrypted content, like many off the shelf Blu-Ray discs for example, CPU utilization will be measurably higher that what you see here. However, both platforms should have no trouble playing back HD digital video.