I'm in here now too with a m4500 but a new version than you have, i bet there will be a lot we can share later on.
Just installed Mountain Lion from original DVD via USB (Purchased and put the 10.8.2 on USB) installed with PCIRootUID=0 only otherwise my screen would go blank.
I did not remove my 8GB of ram nor run any CPUs=X
WIFI - Not working
Sound - Not working
Reboot - Not Working
Bluetooth - Working
Ethernet - Working
DisplayPort - Working
It recognizes my Quadro FX 1800 without a glitch and my 8 cores and cpu speed.