Displayport

[h2323]

I just built a new system with an AMD 7950. I discovered that my graphics card was causing screen fragmenting under load, only if I used the displayport, works fine with HDMI. Is there a setting I am unaware of to make the displayport work correctly?

3dmark caused major screen fragmenting (lines and dots all over, works fine with HDMI)

 

[h2323]

Is it possible that I am using a display port 1.1? and I need 1.2? no markings on cable