iMac freezes, displays lines, overheats

[Aeroshaft7]

I am posting this for a friends iMac. After running multiple apps for about 15 minutes, it gets very warm, typically freezes (rainbow wheel spins forever), or there are horizontal lines that come across the screen.

Could this just be an overheating problem? Open and clean?
Replace Fan?
Video card or Processor going bad?

Thanks!

 

[cwa107]

I would tend to think one or more fans are seized. You should be able to verify by running the Apple Hardware Test:

http://support.apple.com/kb/HT1509

I would buy replacement fans, open it up, have some compressed air handy while you're replacing them. Good luck, the flat panel models (both the plastic and aluminum) are not particularly easy to work on.