The diagrams suggest that AMD’s new cards don’t have any problems reproducing HD video encoded in VC-1 format.
Save for the GeForce 210, each of the tested graphics cards shows a low usage of CPU resources when decoding VC-1 streams, so we don’t want to single out leaders or losers here.
When the H.264/MPEG4-AVC format is used, the overall picture is the same as with VC-1: AMD’s new GPUs offload the CPU well while decoding video and are roughly as good as their opponents, excepting the low-performance GeForce 210.
Judging by the diagram, AMD’s Redwood and Cedar solutions find it harder than their opponents to decode MPEG2 HD, but the difference is 4% can hardly matter much.
AMD’s Redwood and Cedar processors have very advanced video playback capabilities. Save for the lack of Blu-ray 3D support in the junior chip, these GPUs, together with the more expensive models of the Radeon HD 5000 series, seem to be an ideal choice for HTPCs. They have a hardware video decoder and an integrated audio controller. They can output audio in 7.1 format over HDMI 1.3a as well as transfer audio via Protected Audio Path to decode on an external device. They also support a variety of video formats including Adobe Flash 10.1 and offer a wide selection of interfaces (depends on the specific model).
Our tests have shown that the new GPUs can effectively cope with HD video decoding. They can also process two video streams simultaneously, which saves you the cost and trouble of purchasing a top-end CPU.
However, the tests from the IDT HQV Benchmark 2.0 suite suggest that none of modern GPUs can show ideal image quality in all situations whereas special-purpose video chips, e.g. from IDT itself, can do that. AMD and Nvidia will have to do a lot of work on their drivers and, perhaps, even on their hardware to reach the score of 210 points in the HQV tests.