Phoronix: Improving Open-Source ATI Power Management

Red Hat's Matthew Garrett has chronicled his AtomBIOS hacking adventures on his blog that has led to aggressive power management capabilities. By using an AtomBIOS program written by Jerome Glisse to manipulate the clock frequencies, the previously-published R500 documentation, and coding, and he managed to save 10 Watts of power with a Radeon X1300...

http://www.phoronix.com/vr.php?view=Njg2Mg