Like other recent Macintosh computers, the Power Mac G4 computer uses the RAM-in-ROM approach with Open Firmware booting. Software developers should follow the recommended practices for the new approach.
The system software that comes with the Power Mac G4 computer is Mac OS 9 with extensions and control panels required for product-specific features. Features specific to the Power Mac G4 computer are described in System Software Support. For a general description of the Mac OS 9 release, refer to the Technote for Mac OS 9. The technote is available on the Technote website at
With the RAM-in-ROM system software, it is no longer possible to use the box flag to identify the computer model. For guidelines about machine identification, see Computer Identification.
The Power Mac G4 computer can boot from a USB storage device that follows the USB Mass Storage Class specification.
The Power Mac G4 computer can boot from a FireWire storage device that implements SBP-2 (Serial Bus Protocol) with the RBC (reduced block commands) command set.