Power Mac is very unstable

Question

Hello wise Mac people,
My Gigabit is experimenting a lot of instability lately. A lot of programs quit suddenly for no apparent reason (Activity Monitor, for example), something they never did before. The whole thing is freezing over more often than before. And, also more often, the computer just does not come back from sleep.
These problems started after I did three things:
1) Installed a Powerlogix 1.2 dual processor.
2) Started using Camino as my main browser (Camino itself is highly unstable, an issue that everybody seems to have).
3) Upgraded to 10.4.10.
I tend to blame 2) and 3), but you just never know.
Any feedback will be much appreciated.
Peace,
Felix
eMac, iMac, PowerBook, Power Mac Gigabit (running Tiger, Panther, & 9.2.2)   Mac OS X (10.4.9)  

Answer 1

Hi
It's certainly possible, perhaps probable, that the processor upgrade is the culprit. As Tom suggested ideally you should have made one change at a time to make it easier to diagnose any problems. When I upgraded my processor I left everything else untouched for a good couple of weeks, including software updates etc, until I was sure it was completely stable.
It may be that playing video increases the CPU usage and heat generated etc, resulting in the problems. Do other high CPU usage tasks result in similar problems, for example, DVD encoding? I ran a number of applications including the OS X chess game (computer v computer) for a number of hours to check for stability problems.
One option would be to temporarily reinstall the original processor to see whether the problems go away, although ideally you should renew the thermal paste between the old processor and heat sink, otherwise you may get similar problems with the original CPU that end up masking those of the upgrade.
I believe some (perhaps most) third party CPU upgrades use overclocked processors which may be one cause. Normally they're guaranteed to run at the advertised frequency though, and if that's not the case you'd return it for a replacement. I'm not sure whether you can temporarily lower the clock speed via some dip switches on the CPU card. The documentation should tell you, and if that prevents the problems, the chances are the CPU upgrade is at fault. If you contacted PowerLogix/OWC it may be that you could also increase the core voltage etc, although I certainly wouldn't do it unless they suggested it.
Personally I think processor upgrades can be worthwhile, but you have to be prepared to do some testing and perhaps tweaking.