Re: GTX 260/280 Clock Throttling While in 3D Apps. An Explanation.
Isn't the throttling for Aero, etc? ie, light 3D gets the slow clocks, such as desktop and game menus. Probably the same stuttering that bites some Linux users with heavy 3D desktops. Obviously the parts are trying to save power and reduce heat.
Apparently they need an API with ThisIsEasy3D() and ThisIsHeavy3D().