Received and set-up a new 20-inch widescreen G5 iMac this past week and it certainly works fine in ArchiCAD 8.1 (full report on speed impressions withheld as I wait for my 3rd party 2GB RAM upgrade kit to arrive... running with only 256MB RAM and this is affecting overall system performance).
I suspect that AC 9 will be fine but cannot confirm yet as my ordered upgraded from GSCNE has not yet arrived (next week?). I recall seeing a post from a beta-tester that stated 64MB of VRAM was OK and the nVIDIA GeForce FX 5200X Ultra, while initially released back in early-2003, still packs a bit of punch.
Anyone else have first-hand experience with this combination yet?
Senior Associate, Chernoff Thompson Architects
ArchiCAD 16 (firm uses Revit)
Mac OS X 10.10 on Mac Pro (2013)
3.5 GHz 6-core Intel Xeon w/64 GB RAM & Dual AMD FirePro D700 w/6 GB Graphics
1 TB SSD w/20 TB RAID 1
Asus PB287Q 4k UHD 28-inch monitor (3840x2160)