Now has anyone experimented with UNDERVOLTING video cards? I used to have a pentium M ULV that I could undervolt by 25% (no overclocking!) and it ran perfectly. I increased my battery life by doing this.
Most cards I assume could take some degree of undervolting just like they take some degree of overclocking.
It depends on the leakage of your cpu. It won't be the same for all cards even if are the same model.
My 2 HD 6950 are stable at (1.1V, 800MHz stock):
* 0.875V, 600MHz
* 0.930V, 700MHz
* 1.0V, 800MHz
* 1.1V 920MHz
I'm using the 700MHz setting atm, the power drained is very low.