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Resetting EFI firmware password on Intel-based Macs

Sun, 2009.02.01 - 15:50 — müzso
According to the Apple document "Mac OS X Security Configuration For Version 10.4 or Later" you can reset the password if you've physical access to the machine.

Open Firmware password protection can be bypassed if the user changes the
physical memory configuration of the machine and then resets the PRAM three times
(by holding down Command, Option, P, and R keys during system startup). An Open
Firmware password will provide some protection, however, it can be reset if a user has
physical access to the machine and can change the physical memory configuration of
the machine.

This was a well known method for PowerPC based Macs and some did confirm it for newer Intel-based Macs, some denied it. However the above document explicitly mentions EFI-based Macs, so I'd say the document was written "EFI-aware". So I'd assume that since they did not mention anything about the RAM-switching method to work only with PPC Macs, it should work with Intel (EFI-based) Macs too.

P.S.: the above quoted PDF has a nice collection of methods for securing your Mac. You might want to read it or at least parts of it.