With not all H.264 videos being at a high resolution like our first test, we had used another sample H.264 video file that had a resolution of 704 x 576. Below is the Phoronix Test Suite graph when using MPlayer without VDPAU.
When playing back this lower resolution file, the CPU usage had a support level around 20%. The highest we witnessed the Sempron LE-1150 spike was near 30%.
With VDPAU the utilization rate was stable between 5~10%, but at one point it briefly spiked to 40% before returning to single-digit usage. Proportionally, the benefits of VDPAU were certainly much better with the higher resolution H.264 file, but even with this lower resolution video, the CPU usage was sliced in half.