Left my 15" rMBP (mid-2012 model, bought 15 days ago) alone whilst I went out of the room for 5 minutes. When I came back, the screen was covered in these horizontal lines, see attached photos! This is a hardware issue - it exists in Mac OS X, the boot screen and Windows, all running at any (including HiDPI and normal) resolutions. Obviously I will be taking it into Apple but I was wondering if there any solutions. Restarting doesn't fix it. My main fear is that issue could vanish before I make it to the Genius Bar and then re-arise. For anyone wondering, these lines are not appearing because of the camera - they are actually worse when the screen is looked at through your eyes (retinas ) - this is a pretty terrible issue where I had to pay a lot extra for a retina screen and the screen has suddenly become so bad. You can see the lines far better if you view the images below at full resolution.