OS X: Ten Boot Options for Leopard

Multiple shortcuts exist for the various methods of booting Leopard. These ten boot options range from essential debugging tips such as verbose and safe modes to dual booting options. To use these boot shortcuts or commands, hold down the bolded keypress while your system is booting up. If it does not work, you probably did not start holding down the key (or key combination) soon enough.

shift - Safe Mode Booting with the shift key depressed starts OS X in Safe Mode with Account preferences ignored and unessential kernel extensions / kexts disabled.

option - Startup Manager Booting with the option key depressed starts OS X with the Startup Manager which allows the user to select which OS or partition from which to boot.

Mouse button - Eject Media When the user boots with the mouse key depressed, any media in the drive such as a DVD or CD is ejected.

cmd v - Verbose Boot If this key command is held down when booting, all the startup messages that are typically hidden will be displayed. This is an excellent method for debugging booting issues.

c - Boot from CD/DVD Booting with the “C” key held will tell the system to boot directly from a CD/DVD in the drive.

t - Target Mode If the “T” key is held during the bootup, the computer will be placed in target mode. This basically allows the computer to be accessed by other systems as a FireWire drive. Other computers can read, write, or mount the target mode system just like any other FireWire drive.

cmd s - Single User Mode

x - OS X Force boot

n - Boot up from NetBoot Server

link: OS X: Ten Boot Options for Leopard | Mac OS X Leopard | Tech-Recipes