what methode have you used to get to this point? could be allot of things which cause this error. ahci in bios could be off, or you need to add the flag npci=0x2000 to the boot options, use a different usb port maybe the rear ones next to the com ports. or you will need to install a patched IOPCIFamily.kext also PciRoot=1 might be needed or a combination of all methods.