Nvidia cards don't go at full 3d speed if they don't need it (if you're above 35-40FPS in general) you can use the ASUS gpu tweak software and disable 2d clocks...
Also make sure the Vsync is disabled as it will stop the card at 60fps and it may be only 50% or a random value below 100%...
**Games look better with Vsync enabled but don't use (except if gpu limited) the totality of the gpu performance...