iMag G5 Wont Power On After Replacing The HDD

TankBall · May 28, 2022

i started helping out my local free geek about a week ago. they asked me if i could fix a broken G5 iMac. one of the other ppl there replast the old HDD to but some ver. of linux of it. i did power up to install linux but after it asked to restart it never powerd up again. im a a complet lose on what to do and i would like to get this one working. i did make a short video it if someone whats to see it

Needfuldoer · May 28, 2022

Those things are notorious for bad capacitors. (It was the middle of the capacitor plague, and the G5 ran hot.) The motherboard caps in the video don't look too bad, but the power supply might be. LED 1 is on, so the logic board is getting trickle power from the power supply at a minimum.

Frankly it's not even worth the time you've already put into it. It won't run Mac OS 9, and the newest it can run (besides the Snow Leopard PPC beta) is OS X 10.5.8 Leopard.

Try holding the SMU button (the one that isn't the logic board power button) for 30 seconds. I forget if the Mac has to be unplugged, but this should reset the system management unit.

BondiBlue · May 28, 2022

Those iMacs are well known for one thing: bad capacitors. I'm shocked at how well the caps on the logic board look in the video. Those are usually the ones that leak first, but the power supply could also have bad caps in it. You could try opening it up and checking them (ONLY IF YOU KNOW HOW TO DO SO SAFELY), or you could just replace the PSU itself.

That being said, I don't think it would be worth that much effort. Those machines aren't very valuable at all, and I still see them being recycled all the time these days. They were flawed in several ways, and even when running Linux they're just not very powerful at all. A budget smartphone will handily outperform that iMac in every single way, if that helps put it into perspective.

The only G5 Macs that are really worth anything are the Power Mac G5 models, and even then it's mainly just the highest end models that are worth anything. The lower end models aren't very valuable, and none of the iMac G5s ever gained much value over time. Maybe they will in the future, but not right now.