Replaced my DP 1.8 G5 with a CoreDuo 2.0Ghz iMac this past week.
The DP 1.8 G5 did ~60g nodes/sec
The CoreDuo 2.0 does ~ 56.7g nodes/sec
Advantage: Still PPC
The iMac gets to around 169F. A 2.0 G5 iMac I had spiked at 176F during OGR. iMac's are definately not set up for optimal cooling.
Don't think I'll be running OGR on this thing.