Thank you very much black_zion
Funny thing now i installed 12.11 when i change it to YCbCR 4:4:4 and push apply it goes back to RGB 4:4:4 Format PC Standard.I cant save my choice.
Also on 3D games that support HD3D when i activate it my monitor goes blank saying that resolution is not supported.
Also getting random flashes from time to time.