pixellated screen + screen of death

[Mr_Spencer]

My son asked me to look at his friend's iMac G5 and it's in a bad way. When I boot up there are scan lines and coloured pixels everywhere, goes to a blue screen and get the restart message (the one in different languages). I've booted in safe mode and run repair permissions. In safe mode the problem isn't so bad but it's still there, then on restart it has the original problem. I'm thinking it's a hardware problem, but thought I'd see if anyone here had any ideas.

 

[DeltaMac]

If this is an older iMac G5 (no built-in camera), and 1.6, or 1.8 GHz processor, you can turn the computer face down, loosen 3 screws on the bottom edge, and the back will lift up. You can then check inside, looking at the various capacitors (small silver cans) where you might see that some have bulging tops - or even leaking some brown goo....
What you are seeing on the screen is one symptom of those bad capacitors. The logic board needs repairs/replacement to fix that issue. If you _don't_ see any swelling or leaking inside, then it's still a similar problem with the logic board as the culprit. The video chip is known to have overheating problems, and eventually fails with the problems that you see.

 

[Mr_Spencer]

Thanks, will give that a go later.