AMD revealed it's working on a new Dynamic Frame Rate Control feature for its Catalyst drivers. This feature will enable you to limit the framerate with a slider to decrease power consumption. According to AMD director of PR Chris Hook, the difference in power consumption can be mind blowing in cases when the GPU is delivering an unnecessarily high framerate (150fps vs 60fps for instance).
Sounds a lot like V-Sync? Well the way AMD describes it, DFRC is a frame-rate limiter with a slider. Whereas V-Sync makes the GPU spit out frame-rates to match the monitor's refresh-rate. When a game runs, say, 100 FPS, and you enable V-Sync to bring that down to 60 FPS, your GPU is still running at 3D-performance clocks, unless the 3D load is way too low, and the driver decides to change the power state altogether. DFRC probably achieves lower frame-rates by underclocking the GPU, and increasing the clocks, whenever the scene gets more demanding, and the output FPS drops below the target. Hook describes the energy savings with DFRC as "mind blowing." This peaks our curiosity.