iMac G5 Fan Noise
Fortunately, I found an explanation for my new iMac’s noise level: I was using the fast user switching support to enable different environments for my wife and I, for some reason her Safari process had gone up to using 100% CPU, and this was not reported in my activity viewer because by default it only shows the current user’s processes.
So: If the box really has a lot to do, the fans kick in and they are pretty loud. Running at normal load, it’s still louder than the Cube, but you’ve got to have a really quiet environment to notice it.
Don’t be so sure. There are almost 500 posts concerning noisy G5 imacs right now over on Apple’s discussion area.
http://64.233.161.104/search?q=cache:NSapYD447tkJ:www.macintouch.com/imacg5part05.html+%22imac+g5%22+cpu+fan&hl=en&client=firefox-a
it’s all here