PCI is a standard that a lot of companies use. Sun uses PCI as well. Just because they share a common bus architecture doesn't mean it will work. There are two things to consider. The first is drivers. If no driver exists, it probably will not work. The second is when you want the device to work. Apple uses an industry standard, as compared to the PeeCee world; BIOS. If the PCI card was designed specifically for BIOS then you will not be able to use it until the OS is loaded (given a driver exists.)