And you will see either “EFI32” or “EFI64” returned to you.
If you have “EFI32” returned, you cannot enable 64-bit Kernel and Extensions, but you are still able to run 64-bit Applications.
Now, you can either continue to hold “6” and “4” everytime you want to boot, or you can do the following:
Navigate to the following location in Finder:
From there, find this bit of text:
And add arch=x86_64 between the <string> tags, so that you have this:
Save the file, and reboot your machine. If you have a (capable) Mac, you will see “Yes” in System Profiler, instead of “No”.
If you want to boot into 32-bit, just hold “3” and “2” at boot, or edit the file again, and remove that string.
Hopefully this helps some of us with a Mac and Snow Leopard.
Edit: I have realized, that in System Profiler, it may still display “No”.
You can check if you are running 64-bit by default, by checking Activity Monitor, and next to each process, if it’s enabled as 64-bit, it will say “Intel (64-bit)”.