[dnvn]

A friend has experienced the sudden appearance of two vertical bars, each about one inch in width on his desktop. These appear as semitransparent and desktop content can be seen behind the bars. He has been advised that he needs a new motherboard. His iMac is just two years old. Has anybody else experienced this?

[sandbag1]

Do these vertical lines also appear within applications?

[dnvn]

These are not lines but bars. They are on the desktop and look like two columns. They are there always when the computer is on and seem to be semi transparent as all items underneath them are still visible no matter what application is in use. Hope this helps

[Aodui]

I have a similar problem on my 2.8ghz 24inch 2007 iMac.

What I have is two vertical transparent lines, each perhaps only a few pixels wide, that are about an inch apart from each other, on the left quarter of the screen.

It is not always there. Sometimes when I restart they go away. Sometimes when they are there I also have a sort of matte finish on my entire desktop, like the desktop had a 3d surface of paper mache.

My video card, ATI Radeon HD2600, was replaced previously because it made a humming noise when the computer was angled straight forward or down (but not when angled up.)

I'm in law school so I can't take it in for repairs until I get a replacement, but I might try this weekend and ask for a loaner (which sort of requires that the problem be present when they see it at the genius bar.)