This seems to be a issue many people having running a AMD card. It's just not flickering it also goes complete black screen at times. Very often with IE, Visio, and I have an HD 6850. I did some research and seems to be clocking issues or memory speed on the card and I've tried to adjust them but no luck. Hoping the community would help me resolve this issue. Don't have the money to buy a card and probably going back to nVidia in the future. I know the card is a bit old but this problem has started after about 6 month of use.
https://www.youtube.com/watch?v=V0DX4m7tAw0
https://www.youtube.com/watch?v=V0DX4m7tAw0