G73sw black screen during games

Help please, my screen randomly goes blank(black) during games. To get the screen back i have to Ctr-alt-del numerous times. ANy ideas?

Jus to update, it seems it detecting an external monitor whislt the game continues in the background and strangely enough i connected it to an external monitor today for the first time, its been happening since.

 

Are you overclocked?
Your gpu may be unstable
Also defrag the game, believe it or not its helped me before

 

Not over clocked. And its with every game. Screen is on, its just blank. the game continues in the background.

Doesnt feel like the card is unstable, just feels like it keeps trying to switch to an external.

 

Does FN+F8 help?

 

Nope, no luck. Connected to external when the laptop is black screened and image appears on external, all working fine. Try to switch to laptop, nothing.

Also, i updated drivers to current.

 

sorry about that, is this situation also happening during normal movie watching or surfing on internet ?

and it seems there is no any warning, I dont know whether it can help or not bur same happened to me on Dirt3 during game play screen became black " but it was overclocked GTX 460 M " and when I restart the game just sound came from back and screen was green I reinstalled game and it fixed.

but every single game if you have same thing then it is better to check DirectX files " reinstall on game folder best idea with game " or C++ files which comes with game these are can create such problem and if you also update Win7 with service pack this may create such promlem too. In some configiration Win7 SP1 may cause many various promlem randomly