PRAM batteries die quickly

I have a PowerMac G5, bought in 2005, 2 GHz CPU, 2.5 GHz memory.

A while ago the screen froze, the fans got noisy. I replaced the PRAM battery, it lasted about 10 hours before the screen locked again and fans got noisy. I tried restarting the next day, got a bit more life from the battery then it died completely.

I've got through about 10 batteries since then, each does the same. I've reset the PMU and held down keys during startup to get two chimes.

A while ago (since problem started) I'd left a PRAM battery in there for a few months without switching mac on. When I tried it it was dead, I then took out the battery and it worked fine but crashed after a few hours. It doesn't normally work without a battery in there.

Any help would be very greatly appreciated.

PRAM batteries should actually last somewhere in the neighborhood of 3-5 years...even more in some cases. Something very unusual is going on with your PM G5 if you're going thru PRAM batteries as quickly as you describe.

- Nick

I agree with Nick. It sounds more like a defective power supply in that Powermac which is eating your PRAM batteries. You need to cure the cause of the problem not the symptom. Go to the ifixit web site and do some trouble shooting with their hints and diagrams.