Game minimizes at regular intervals

[Faun]

I am encountering this weird problem in Win 7 64 bit.

Playing games (BF bad company 2, Team Fortress 2) in steam works fine for few minutes and then the game minimizes in the middle of action. Sometimes game windows loses focus. Happens with every game.

What could be the problem ?

I suppose I changed some of the setting in NVIDIA control panels for Anisotropic filtering, triple buffering, ambient occlusion etc

 

[theserpent]

Well i too faced this problem with Tf2.It appeared to be a problem with the resolution i was using.i changed to native res and it became proper