Hy everybody! Since a week I'm experiencing some issues on my 27" iMac (mid. 2011). There are three strange things that occur. Screen flickering. Vertical lines (blue or gray) Vertical lines magenta transparent White screen Black screen It all started with a first screen flickering, and after a reboot it worked again. Now, I'm getting screen flickering and right after vertical lines. Sometimes they're blue, sometimes gray. as of shortly i was able to get to the login-screen and after entering my password, the flickering and the vertical lines came up. Now the flickering starts as soon as the login screen or the rotating circle appears. What I've done so far: Reset PRAM Reset SMC Start up in save mode (at first i was able to boot up here, but now i cannot) Btw. I'm out of warranty :-( I'd like to fix that myself if the problem is not the logicboard I'v made some photos and videos to show you what I'm exactly talking about. http://files.adisdurakovic.com/imac/pic1.jpg http://files.adisdurakovic.com/imac/pic2.jpg http://files.adisdurakovic.com/imac/pic3.jpg http://files.adisdurakovic.com/imac/pic4.jpg https://www.youtube.com/watch?v=byRJhXsh1d4 https://www.youtube.com/watch?v=-cJBkydH3qI I hope someone can help me. Thx!