Hmmmm...from what I can find, the POWER
(Performance Optimization with Enhanced
Risc) architecture was not fully 64 bit, but
its FPU did indeed have 32 64 bit registers
(branch and integer registers remained 32 bit).
I'm not sure whether or not the 64 bit FPU
architecture was carried over to the PPC
line of processors before the 620 (the first
true 64 bit PPC) but if so, it may explain why
the early 66mhz 601's stomped the 66mhz
'060's in the FPU benchmarks, while remaining
relatively on - par or even slightly slower
in other benchmark areas.