You can boot a Mac from FireWire, the ability to boot a Mac from FireWire is most useful when youre experiencing problems with your Mac and need to run system diagnostics, or simply access the system but cannot do so through the computer itself. Purchase a FireWire flash drive or a hard drive with a FireWire interface and the appropriate connector cable, and then install a Mac operating system to allow the Mac computer to boot from that FireWire device. You can also use another Macintosh computer as a FireWire drive, provided that it has the appropriate FireWire connector. Follow the simple steps below

Use FireWire When Macinstosh Wont Boot On Its Own

Locate Your Mac Computers FireWire port. It will usually be located near the USB port and will be just a bit narrower and taller than USB ports, with angled corners on one side of the port.

Plug the FireWire connector for your FireWire drive or device into your Macintosh computers FireWire port.

Hold down the Option key as you power your Macintosh computer up.

Select the FireWire drive from the list of available boot-up options that displays on your Macintosh screen.

Click the right-facing arrow to select the FireWire drive and finish booting your Mac from it.

Operate FireWire When Macintosh Will Boot On Its Own

Turn your computer on and let it boot completely.

Locate your Macintosh computers FireWire port, as above.

Connect the FireWire connector for the FireWire drive to your Macintosh computers FireWire port.

Open a Finder window to make sure that the icon for the FireWire drive is displayed under Devices in the Finder window.

Open the System Preferences dialog for your computer and select Startup Disk from the list of System options.

Select the FireWire drive you want to boot with.

Click Restart to reboot your computer using the FireWire drive.

Utilize A Macintosh Computer As A FireWire Disk

To use Macintosh computers as FireWire disks themselves, hold down the T key during system start up. This forces the system into FireWire terminal mode, at which point it can be connected to another Macintosh computer via a FireWire cable and used as a terminal or drive disk.

• This is a useful technique for transferring specific data from an old computer to a newly purchased computer. Just boot the old computer in terminal mode, connect it to the new computer, and transfer only the data you want to transfer, instead of transferring everything with the Migrate utility.
• This technique works for almost all Mac computers, in both desktop and notebook models, with G4 or faster processors. The one notable exception to this is the Power Mac G4 model with PCI graphics, which does not support FireWire booting.

Note

Some FireWire drives may require you to install special system software to your Macintosh computer before booting the computer from the FireWire drive–always check the product documentation to be sure.