Thanks for the replies. The spec is: Asus P5GC-MX Intel Pentium Dual Core E2140 4GB Ram Nvidia 8500GT Seagate 250GB SATA HD The M/B uses an Intel 945GC chipset, Realtek ALC883 sound and Atheros L2 network adapter. I have 2 of the Nvidia 8500GT cards and both have the same symptoms, my Linux box works fine with either of them. I can't get the system to boot in safe mode with it installed in the system. I have tried swapping it out for a Nvidia GT520, this card will boot into safe mode with the npci=0x2000 switch but not boot normally, just hangs. Thanks.
I'm trying to get my first ever install of OS X running, 10.8. I could not get it installed with my PCIe 8500GT 256MB as the screen would just go black during the install. I took the card out an got the install completed with the built in Intel graphics, although it used low res 1024x768 resolution. I'm now trying to get the Nvidia card running, I cannot get to the desktop with this card installed. I have put the NVEnabler_64.kext in the extensions folder and inserted the correct device ids for the card but on reboot I just get a black and white screen with random dots (http://biketech.org/pics/screen.jpg), although it appears from the disk activity that the system is running in the background. The device id for the card I managed to get from my Linux install is 10de0421 which in the scripts appears to be 0x042010de&fff0ffff this mask looks fine for my card. Any advice on what to do next would be appreciated.