Aug 19









Everybody knows about some of these boot key combinations, but some of the more obscure combinations have been long forgotten (like how many of us have a Quadra AV and use a TV as a monitor!) – Check these out, you may need one of them someday!

  1. •C : Forces most Macs to boot from the CD-Rom drive instead of the internal hard drive. Only works with Apple ROM drives and with bootable CD discs.
  2. •D : Forces the first internal hard drive to be the startup disk.
  3. •N : Netboot (New World ROM machines only) – Looks for BOOTP or TFTP Server on the network to boot from.
  4. •R : Forces PowerBooks to reset their screen to default size (helpful if you’ve been hooked up to an external montior or projector!)
  5. •T : Target Disk Mode (FireWire) – Puts machines with built-in FireWire into target Disk mode so a system attached with a FireWire cable will have that device show up as a hard drive on their system. Very useful for PowerBooks!
  6. •Mouse Button Held Down : Ejects any mounted removable media.
  7. •Shift : Disables all extensions (Mac OS 7-9), or disables Login items when using Mac OS X 10.1.3 or later. Also works when booting Classic mode up just like you were using the OS natively.
  8. •Option : When using an Open Firmware “New World ROM” capable system, the System Picker will appear and query all mounted devices for bootable systems, returning a list of drives & what OS they have on them. On “Old World” systems the machine will simply boot into it’s default OS without any Finder windows open.
  9. •Space bar : Brings up Apple’s Extension Manager (or Casady & Greene’s Conflict Catcher, if installed) up at startup to allow you to modify your extension set.
  10. •Command-V : Boots Mac OS X into “Verbose Mode”, reporting every console message generated during startup. Really shows what’s going on behind the scenes with your machine on startup!
  11. •Command-S : Boots Mac OS X into “Single User Mode” – helpful to fix problems with Mac OS X, if necessary.
  12. •Command-Option : Rebuilds the Desktop (Mac OS 7-9).
  13. •Command-Option-P-R : Erases PRAM if held down immediately after startup tone. Your machine will chime when it’s erased the PRAM, most people will hold this combination for a total of 3 chimes to really flush the PRAM out.
  14. •Command-Option-N-V : Erases NVRAM (Non-Volatile RAM). Used with later Power Macintosh systems mostly.
  15. •Command-Option-O-F : Boots the machine into Open Firmware (New World ROM systems only).
  16. •Command-Option-Shift-Delete : Forces your Mac to startup from its internal CD-ROM drive or an external hard drive. Very helpful if you have a 3rd party CD-ROM drive that is not an Apple ROM device.
  17. •Command-Option-Shift-Delete-#(where #= a SCSI DEVICE ID) : Boot from a specific SCSI device, if you have your 3rd party CD-ROM drive set to SCSI ID 3, you would press “3″ as the # in the combination

And, the obscure ones :>) Older computers only, on some.

  1. •Command-Option-I : Forces the Mac to read the disc as an ISO-9000 formatted disk
  2. •Command : Boots with Virtual Memory turned off.
  3. •Command-Option-T-V : Forces Quadra AV machines to use TV as a monitor.
  4. •Command-Option-X-O : Forces the Mac Classic to boot from ROM.
  5. •Command-Option-A-V : Forces an AV monitor to be recognized correctly.

Leave a Reply

preload preload preload