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Mac Monkey · Apr 28, 2012, 08:16 PM

Hello,

I have a G5 Imac that now won't turn on?

The strange thing is that the other day it turned itself on for no apparent reason and was working perfectly for several hours? We had a power cut and after the power came back on the Imac wouldn't?

Any ideas?

Thanks for any advice you can give.

Mac Monkey

MacNNUK · Apr 28, 2012, 08:56 PM

Check the fuse in the plug !

A power surge may have blown the fuse...

abby · Apr 30, 2012, 04:04 PM

try this: iMac G5: Troubleshooting when your computer won't turn on

Doc HM · May 1, 2012, 03:44 AM

Almost certainly the PSU. Easy to swap out, very hard to find replacements at a decent price.

chipchen · Jul 22, 2012, 01:54 PM

First, do this: http://support.apple.com/kb/HT1767

If not, then it's likely the PSU needs to be replaced. At this point, it MAY not even be worth replacing... but if you need a computer and/or the data isn't backed up, then you may have no choice. The Apple store may have deemed that model too old to repair anymore... so you might have to find one off ebay or something.