Wierd black boxes on screen help please

[pathosmusic]

This has happened to me a few times in the past year... I am not really sure what it is. It only stays on the desktop, when i open new windows such as firefox or any other program, the boxes dont display. Its almost as though they are on the background picture of my desktop.

If i restart they go away, nothing else fixes it.

Any ideas on what it is or how to fix it?

Macbook 13" black

 

[ergdegdeg]

Edit: as seen from screen shot, it's not VoiceOver. Looks more like a graphics card issue to me.

 

[blackburn]

Check ram for defects. May not be an graphical chip defect, since the ram is shared with the graphics card. You can try to swap the ram sticks or (and) run apple hardware test.

If you swap ram sticks and the problem goes away you most likely have faulty ram.