[kazlivsjy]

Hi. I have just bought a Power Mac G5 QUAD and after burning so many bucks, I wasn't precisely delighted to find out that there's something hideously wrong about the unit ; as soon as I get the CPUs to work hard I get kernel panics of all sorts. After a little bit of guesswork and testing, I found out my suspicions were right: the CPU(s) overheat and become unstable beyond 70 degrees celsius / 160 degrees fahrenheit . Why do they overheat? Easy question: the Fan Control Unit doesn't put the fans to work at all! The fans DO work; I can hear them clearly at system startup; after a system crash, when the FCU doesn't receive any feedback from the OS, it sets the fans to full speed and sure they make a hell of a noise. But, when OS X is up, the fans remain ALWAYS at the minimum speed, no matter how heavy the CPU load and system temperature. I reckon this is not normal. Apple's full hardware test reports no problem, though. I've contacted Apple about this, and after all kinds of testing and attemps to fix the problem (OS reinstall, PRAM and NVRAM reset, summoning of supernatural powers, etc...) they've agreed to declare the unit D.O.A., and I'm getting a replacement. But, anyway, do anybody have a clue what can be wrong with my computer?

[Big Mac]

That is odd, sorry you had that experience.

[Zubir]

That is odd. Usually, the problem is the opposite of your problem, i.e. the fans blow at full speed constantly.