I upgraded my Power G4 DC 867MHz to DC 1.42GHz. I have replaced the processor board, logic board, heatsink and graphics card with the original parts from a DC 1.42GHz G4. It's running 10.5.8. Now the computer freezes either under heavy load or after being idle for hours. I suspect it's due to overheating. The fan is not spooling up even when 2 processes of superpi are running. The vanilla applefan.kext has the lowest threshold of 14,592 = 57 celsius, and iStatPro shows a CPU temperature of 54 celsius tops, so I guess that's why the fan is not blowing hard. But when I reboot the computer as soon as it freezes, the fan starts whirling up and eventually slows down at the welcome screen. Do I need to tell the OS to re-learn the new hardware?
