So richtig schlau bin ich mit den gefundenen Google-Beiträgen nicht geworden.
Vermutlich ist es kein wirkliches Problem.
Hier aus einem Beitrag:
The error message is coming from the following code in the function 'installChipFaultHandler' in the file U3.cpp (
http://www.opensource.apple.com/darwinsource/10.4.5.ppc/AppleMacRISC4PE-185.0.0/U3.cpp)
// We should have a chip fault signal on U3-Lite, U3-Heavy and U4
if (provider->getProperty(kChipFaultFuncName) == NULL)
{
if ( IS_U3_HEAVY(uniNVersion) || IS_U4(uniNVersion) )
IOLog("AppleU3: WARNING: platform-chip-fault expected, but not found\n");
return kIOReturnUnsupported;
}
I'm assuming that your iMac is a PowerPC iMac, not one of the new Intel-based ones? Is that right?
I still don't know what the base cause of the message is, but it seems likely to indicate a small bug in the above code (i.e. its assumptions about the hardware) rather than a fault with your machine.
You shouldn't worry too much about this message unless you have actual problems with the machine.
