Windows 7 - Radeon HD 4850, Black Screen

So i have had my radeon hd 4850 512mb OEM card which i bought new since August 2011 and soo far the performance is great and i have only had 1 problem which coexists till this day.

The problem is like no other i have ever seen im my life. Example of the problem and when it occurs. Well when im playing a game, any game for that matter and its dark anywhere in the game such as down a hallway. The Gpu stops sending signal to my moniter. And if i look in any direction where there is light of color it would resend the signal back to my monitor and it will display video. I currently have the latest drivers installed and have tried every possible fix that i could but nothing has changed. Even tested the gpu in other mobos.

Here are my Specs.
CPU - Phenom X4 9150e 1.8GHz
MOBO - ASUS M3N78 PRO
RAM - 4GB DDR2 @800MHz Running in Dual Channel Mode
GPU - OEM Radeon HD 4850
HDD - SEGATE 750GB SATA 3 @ 7200RPM
PSU - Rocketfish 500Watt WPS2 - it meets all the specs to run my system so this is not the problem before you ask.
OS - Windows 7 64 - Bit Home Premium


Please someone help me