Yesterday I was working on my iMac 27" Late 2009 with OS X Mavericks 10.9, suddenly Google Chrome's tabs started to flicker. I thought restart would stop this – but after the computer boot up again it was even worse.
The boot screen and System restore are looking fine (So i don't think the monitor hardware is the problem).
I even re-installed OS X again, but still no change.
Here is some images I took of my screen.
also, the login screen is even more messed up:
Please advice!! I don't know what to do!!!
Is it a known problem? any known solution?
Best Answer
Based on your images, this is either a graphics processor issue or a display issue. I highly suspect the former. Either way, it is a hardware issue for which no online troubleshoot exists.
To test, however, the next time it occurs, take a screen shot. If the distortion appears on your screenshot, then the problem is with your graphics processor and you to get your logic board replaced. If the distortion does not appear on the screenshot, then the issue is with your display and you need to get your display replaced.
Best of luck.