The Current State Of Radeon Power Management

When using X-Video to playback a 1080p H.264 video sample (Big Buck Bunny) in MPlayer, the CPU usage was not really affected by the GPU clock speed due to the little impact X-Video has when paired with a modern CPU. However, X-Video with the Catalyst driver did go through slightly more CPU cycles than the open-source driver.

The Radeon HD 6950 GPU frequency during this video playback process was obviously unchanged with the static stock/low/medium/high power management states, but to note is how the Catalyst driver and dynamic power management modes were handled. The HD 6950 with the open-source "DynPM" mode had the card running at 500MHz constantly while the Catalyst driver bounced between the 250MHz, 500MHz, and 800MHz states.

With the Catalyst driver bouncing between power management states, it ended up being warmer than the Radeon DRM forced into the lowest power state for the duration of the test, but was cooler than the rest of the configurations tested.