Hard disks and fans are common bad buzzing noises. I hope you have what you can't lose on backup. Hard disks are cheap to replace before they go south.
Bob
So my powermac g4 was making a buzz noise and having trouble booting up. I proceeded to repair the disk permissions under disk utilities and it helped the booting problem. But I still hear the buzzing, is there anything I can do to figure out what it is?

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