iMac Firmware Update

The iMac Firmware Update 4.1.9 will only run on iMac computers with slot-loading CD or DVD drives running Mac OS 9.1 or later from a local drive. If you are using Mac OS X you must boot from a local Mac OS 9.1 or later writeable partition (not a CD, or network disk) prior to following the update instructions. Firmware updates are also available for Power Mac G4 and Power Mac G4 Cube models. Firmware Update 4.1.9 includes improvements to starting up Mac OS X from the local hard disk, Firewire target disk mode, starting up from the local hard disk, network startup, and system stability. This update also adds support for additional security options which allow the Open Firmware to be password protected. Before you install the iMac Firmware Update 4.1.9, read the instructions below. You may want to print them for reference.