U2713HM, distorted display

Hi 

My Dell U2713HM start distorted display whole screen look analog green and purple pink haze. Sometime monitors goes black and flicker and comeback again.  Using Dual DVI and Asus HD 6770 video card.

Tried Dell monitor factory reset and diagnosis ( no problem found)

Tried uninstall driver from safe mode with disabling display adapter and reinstalling from windows update not work. Sometime work for 10/15 minute and start haze but 1920x1080 work fine. 

Tried to compatibility mode (windows with latest driver from AMD Site) in compatibility mode max resolution is 1280x1024, and if I switch to 1600 its starts to flicker.

Thanks