G5 Freezes

Hello there!
i'd like to ask for some advise. I have a PowerPC G5 with 10.4.11 system that freezes all the time and i need to force a shut down to make it work again. It happens at least twice a day and then it works normally. Can someone please tell me how i can fix this problem?

Thanx

Run disk utility from your install discs and verify the permissions and then the HD.
Once you've done that, you should also zap the PRAM.
Reboot and see how it goes, and then report back if it's still doing the same.
Be aware that G5's do suffer with logic board issues, so it could be the start of that, in which case you don't have many options, but try the above first.

Is it an Imac or Powermac? The G5 is a great processor, but was designed for much more ventilation and cooling then apple provided. If it is an early iMac G5, these suffer from bad cooling iirc because of air cooling. it could also be a program that is written badly and leaking memory, any program with which it behaves like this in particular?

Hello guys!
thank you for replying. Well the machine is a Powermac and it freezes during any kind of process, does not have a particular program which it does it with....i'm gonna try your advises and i'll let you how it goes!
thanks again