I play the new Need For Speed under bootcamp win7 64bit, and I do nothing else with this system, just for gaming, (so it's very clean). However, sometimes after I startup, and launch the game, the game is very very slow, it looks like running on the HD4000 not GT650. I tried to restart the computer or reinstall the graphic card driver and it does't work. Every time when the game runs smoothly, I can hear the fans start working when I see my car. When the game is slow, the fan is not working. I assume it's because the hybrid graphic cards does not switch to GT650. Is there anyone have the same problem or have a solution? maybe to force windows using GT650?