1. If you are running a supported system (Intel Core-based CPU), then when you get to the boot prompt (Press any key to enter startup options, press a key and type:
npci=0x2000If that doesn't work, try npci=0x3000. If you still get the same error, try typing PCIRootUID=1 before each of the commands listed previously:
PCIRootUID=1 npci=0x2000and also npci=0x3000 if the former doesn't work.
2. If you are running a unsupported system (all AMD and non-Core Intel CPUs), update the kernel for 10.6.8 (kernel version 10.8.0). This kernel can be found here and on nawcom's blog.
3. If you are running a unsupported system and you are getting this error with the new kernel, use the solution given for supported processors.