I had a friend with an old Dual 1.25Ghz G4 quicksilver with 1.5GB of ram that went on the fritz. It was 5 years old and they told him it was the HDD. So he decided to buy a new MacPro instead of sinking more money into an old computer. (recently added 1GB of ram and had a new powersupply installed) He offered to sell me the hulk for $100 to cover shipping so I took him up. I had several good EIDE 80 and 120GB HDD's in a tub from old PC's so I figured cheap rendering node for my Xgrid.

Well I got it and turns out the HDD was fine. I did a clean install of OS 10.2 then upgraded to 10.4 with the existing 160GB HDD and have had no real problems.

The one thing I do notice is that one of the fans is a little noiser than my other G4 tower (1.33Ghz g4 with 4GB of Ram) and sometimes the fan will power down for a second, pause, then I get a beep like a Biegebox PC starting up and the fan starts up again. It sounds exactly like a single CMOS/BIOS beep on a PC. Almost like the fan stops and reboots.

I've been around macs for a while and I've never heard a tower's fan powerdown and reboot like this. Any ideas? It's not affecting anything (as far as I can tell, just something that I noticed)

It's not visibly affecting anything yet, fortunately. However, if the fan is dying, you will have to replace the faulty fan or you will probably run into some real troubles.

Maybe the "beep" you ear is simply a warning "fan problem", problem solved because th fan restarts after a small time failure.

I figured out what it was, one of the HDD's in the machine was goofing up. (the original 80GB drive that came with the machine). I managed to download the drive to an external back up and then went to Best Buy and picked up a new 160GB (largest EIDE they had) to replace it with. Not a bad buy for $100 and added 80GB of space to the system. Not sure what I'm going to use that for since it's just going to be a dedicated rendering node for Blender and Fincal Cut projects....