Extremely Strange Display/Refresh Rate/Graphics Problem

[Frazelman]

Hi, so i've had this issue for a long time now 5+months however now I'm in need of urgent help. I will describe the problem. I use a BENQ XL2411T 144Hz Monitor with a DVI Cable connected to my Nvidia GTX 780 Graphics Card. suddenly about 5 months ago i was unable to use a refresh rate above 85Hz properly (even at 85Hz looking at anything dark just makes the screen go crazy). The higher I choose the refresh rate the worse the problem is. Furthermore, decreasing the brightness of the monitor makes it even worse. Also if I look at anything black like a background or anything dark within a game etc it makes the problem worse. (this is NOT a cable issue I've already tried replacing it)

I will link a video showing each of these problems here:

https://www.youtube.com/watch?v=wvov2Kw4bFc&feature=youtu.be

Full system:
BENQ XL2411T 144Hz Monitor (not overclocked)
AMD FX 8350 4.3Ghz (not overclocked)
Nvidia GTX 780
16GB 1333Mhz Corsair Vengeance RAM (not overclocked)
120GB Corsair SSD +2TB WD Storage
850W Corsair PSU
ASUS Sabretooth 990FX Motherboard

 

[Yeshyz]

I have exactly the same problem with same screen and graphic card please help us , its been going for 2 months now and its really annoying , thank you