Can't Play Game In Full-Screen, Only In Full-Screen Windowed.

[xiFuSiioNz]

I have this problem at the moment were I cannot play the game in full-screen. If I try to play in full-screen the screen is just black, I still have sound just no picture. So the only way I can play is in full-screen windowed, also since this has happened I'am getting lower fps in game, I used to get a constant 75 fps with v sync (my monitor has a 75hz refresh rate) now it drops to the 40-50s sometimes lower. It just happened out of no were I Havant installed any new software my graphics drives are the latest so i have no idea why it started doing it.

 

My system specs are:

 

CPU:3770k

 

GPU:GTX780ti

 

RAM:16gb