Well using cool & quiet with optimized voltage will probably do more. I use K10stat to set my 7750 at p-state1 1400mhz with .9v to CPU and 1.05 to NB, that get it down around 30W. You can change each P-state in K10stat, which is nice, also you can click on the current clock speed for each core to lock it in one P-state, so no annoying back and forth between states when the lower state will be good enough, just at a little higher load %.