Measuring CPU usage during HD video playback: ATI vs. NVIDIA
 

ATI's 2900 XT lacks the hardware decoding engine ATI built into the rest of the HD 2000 and HD 3000 series, so its performance (or lack thereof) establishes a comparative baseline for the other video cards we tested. CPU usage when paired with the 2900XT is also a useful reference point for anyone planning to re-purpose an older video card with limited (or non-existent) hardware decode capabilities. While our 3GHz Conroe Core 2 Duo handled it ably enough, performing the entire decode process in software required a significant amount of CPU power.

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