Need G5 Help: Something running constantly

Hi, my parents have a Dual 2.5 GHz PowerPC G5.

It was originally very quiet except when:
- lots of programs were running
- iPhoto was importing pictures
- streaming videos were being watched
or
- a program was not responding, etc.

At this point, a fan and something else (the second processor, I’m guessing? Don’t know much about these things) would turn on. It was loud. You could hear it accelerating until a constant speed at which it would stay until whatever it was doing was done eg. until IPhoto was done importing or whatever program was not responding was force quit, etc.

The problem now is that it is like this all of the time; from the second OS X starts up to until the computer is shut down. It is very loud and irritating.

Can someone please help me troubleshoot and figure out what is going on here? How can I detect what is causing the second processor or whatever it may be to always be running?

Welcome to Mac-Forums SC87!!

I would start by turning the machine off, opening the case and making sure that the fans are not clogged with dust. This happens frequently and reduces the efficiency of the cooling system, causing it to work harder (thus louder).

Then I would start it up and use Activity Monitor (in your Utilities folder) to check for any constantly running high CPU usage processes. If you find one, and you don't know what it is, it is time to dig deeper.

Third, I would get the iStat Pro widget and check out the various temperatures inside your machine. Post these back and we can comment on whether they seem normal or not. I am going to guess that your machine is running pretty hot.

These are some "get started" ideas. Post back with your results and we will walk with you through the process of returning your Mac to a more blissfully silent state.

EDIT: BTW, I have a dual 2.3, and no matter WHAT I am doing, or how heavily I load the machine, I have never heard the fans rev up. It is a wonderfully quiet machine.