Strange Streaks On My Mac Desktop

[HadItWithWindow]

When viewing an uncluttered desktop I see three or four rainbow type lines that look like someone took an eraser and made a few sweeps on the screen.

I do not see those marks at all while viewing this screen on MacRumors but on some web sites it is very evident.

What could cause those permanent streaks? They appear about in the upper left quadrant and I think there are three. Only one is very noticeable. It looks like I took an eraser on the end of a pencil and smudged the screen.

Similar to what you would find if your eraser on the pencil is dirty and you tried to erase on a piece of white paper.

Any ideas? And no, I wasn't near my machine with an eraser I'm wondering if this could have happened when I transported my machine to repair a few months ago?

 

[FrankHahn]

Either your video card or display can cause this problem. To find out, use another healthy display with your computer. If no problem occurs with this display, then the problem was caused by the video card; otherwise, it was due to the display.