FPS suddenly cut in half.

[Towowo]

Lately when trying to play it seems like the game only runs half as well as it used, I used to get a solid 30-40 FPS, but now it runs in 15 FPS. The odd thing about though is that the game runs at the former with no problems when the game window is inactive.
The moment it becomes active the FPS drops again.

[Brightwizard]

Nvidia driver was recently released - this may be the culprit. Who knows.

[Squa11_Leonhart]

blast your cpu fan/heatsink with compressed air

[Towowo]

I have considered this but however this computer is fairly new and basically a week old, if dust was going to be an issue I think I'd have to hurt myself.

[erulisse]

newest nvidia driver either crash FF completly or cut fps in half after "graphic driver crashed and was recovered", with earlier versions it usually could work after that
so if your game stops for a second, or you get black screen then your fps is cut in half its most likely this, and there is not much you can do with it (sometimes clocking down the card helps) :/ also radeon drivers can crash this way