This is how my screen looks like after 5-10 mins being plugged into my macbook 2011 i7 16gb ram:
Havent found a fix for this yet and the pic shows the first symptoms, after 15 mins the screens goes unreadable.
tried ML and Mavericks, driver 1,8, 2,0 and now 2,1 and nothing seems to work.
incase the image wont show up here a url for copy paste
http://sv.tinypic.com/view.php?pic=k...8#.Uvov7mTuI2U
edit: theres no specific program related to this, this occurs even if i have no program running and i dont do anything with the computer.