Running one cpu instance:
XTX 512mb 756/900 5:16/frame(sweetspot on stock volts under water for my card
XTX 512mb 648/774 5:46/frame
CrossfireXT 512mb 620/720 5:52/frame
XTX and Crossfire @ 690/765(craptastic mastercard!!!)running multi-gpu two instances, no cpu instance 5:58/frame AVG(times differ due to multi-gpu client only using one cpu for data shuffling, IMHO, no confirmation form Stanford yet)
XTX and Crossfire @ 690/765 running multi-gpu 2 instances, 1 cpu instance 6:15/frame to 7:45.frame, dependant on what unit the cpu is crunching.
XTX and crossfire @ 500/600(stock 2D) running 2 multi-gpu instances, and 1 cpu isntance 9:39 to 12:06/frame, once again dependant on cpu WU.
All tests done on D975XBX, 400FSB/1066 strap, Conroe @ 400x9, ram 1:1 4-4-3-4-28-6-8-5-4-6(memset timings). I'll fill in missing configs and such as time allows.