First, a disclaimer: Don’t do this unless you feel confident and safe to do so :). This will void the warauntee on your G4, big style, but hey… It’s so old I doubt anyone would repair it anyway, right?
With that said, making an old Apple G4 quieter is a fairly simple job. There are three fans that need replacing, two 60mm fans in the power supply, and one 120mm fan that cools the CPU. Some would argue that the two smaller fans make the bulk of the noise, but my G4 is in an audio environment, so I wasn’t taking any chances. Besides, the bearing on the 120mm fan was wearing out and emitting that telling grind of death noise.
The best on-line piece on dealing with the G4 noise is on xlr8yourmac (the article is no longer online). Normally I get components for quieting machines from QuietPC, but because of the special fan sizes this time I went to FrozenCPU (an insanely large collection of PC bits and pieces, but a carbon foot print fail, since my fans went: China -> US -> UK).
It turns out you can actually get a full kit here, but not so cheap.
I ordered a SilenX 120x120x38mm – 18dBA – 90CFM iXtrema Pro Fan and two Cooljag Everflow 60mm x 25mm Fans with grommets. Just enough to hush the mac, although potentially not enough airflow for a fully loaded system. You can laugh at my exploits in these Qiks:
Part I – wind noise:
Part Ib – going in:
Part II – getting it out:
Part III, the result: