I can no longer get my iMac to boot into open firmware. When I restart with the cmd-opt-o-f keys held down it will not go into open firmware. It just boots normally into Leopard. What could be wrong? I am currently experiencing major system slowness so was going to try the reset-nvram, set-defaults combo just for kicks before I backup and attempt a clean install.
iMac Core 2 Duo 2.16 GHz,
Mac OS X (10.5.4),
2GB RAM
There is no Open Firmware on Intel Macs. COMMAND-OPTION-O-F does not work. Intel Macs use EFI not Open Firmware. If you need to access single-user mode then boot using COMMAND-S.
So, does the old "zap the PRAM" which is now listed in the chart as Reset NVRAM actually do the same as the older open firmware reset-nvram command? What about set-defaults? Can you enter these commands in single user mode? I never tried that.