Q: iMacs do not have expansion slots, so there is no PCI bus on an iMac, right?

A: That is not correct. Although iMacs have no expansion slots, they do have a PCI bus. The PCI bus is the I/O bus used by Apple today with or without slots. PCI and Open Firmware were introduced on the PowerMac 9500.

Developer Documentation | Technical Notes | Development Kits | Sample Code