>>> They lack the hypervisor included in other Power 4 based cpus

>> The CPUs of all G5 Mac models include a hypervisor,
>> see past discussions :-)

> I thought that was disabled

Yes, as we discussed back then, on G5 Macs the PPC970's hypervisor is disabled by the machines' firmware. Yet, this doesn't render the hypervisor nonexistent. It's there in the CPU and can be used on other (non-Mac) PPC970-based machines (and could be used on the Mac if someone found a way to alter the relevant firmware bits).