Hosting and bandwidth provided by MacAce.net.
To be notified of new Q&As, sign up for EveryMac.com's bimonthly email list.
If you find this page useful, please
Bookmark & Share
Can the MacBook Pro boot from an external Firewire or USB drive?
Apple's Support Site simply says "Don't Start Up from an External USB Device" as "under Mac OS X, Apple does not support starting up from USB devices". Apple's Knowledge Base also states that "Mac OS X installation discs that came with a PowerPC processor-based Mac won't work with an Intel processor-based Mac, and vice-versa, even if both Macs came with the same version of Mac OS X."
Likewise, prior to the release of the MacBook Pro, readers of the MacInTouch website wrote that they were told by Apple representatives that the Intel-based Macs can boot from external Firewire "400" hard drives but not from USB 2.0 hard drives.
In particular, a reader by the name of Daniel Fazekas noted that the hard drive "must be reformatted in a new partition format specific to Intel-based Macs called GUID Partition Table (GPT). This is an option you can select in the Disk Utility software [installed on these systems]."
He continues to note that "disks using the Apple Partition Map (APM) scheme could be read. . . on Intel-based Macs, but [cannot be used as boot drives]. Similarly, drives reformatted to use GPT won't boot on PowerPC-based Macs, and will only be readable on Macs running MacOS X 10.4 Tiger."
In a nutshell, Intel-based systems, like the MacBook Pro, can boot from external Firewire drives, and can boot from external USB drives as well, provided that the drive is formatted appropriately (GPT) and a compatible version of MacOS X is installed. Nevertheless, as Apple does not appear officially to support booting from non-Firewire external drives using MacOS X, it probably is wise to use Firewire.