Well, I am a tad bit bummed out. I just found out that my Mac Pro has a 32bit EFI (think BIOS) and I cannot boot into 64bit mode. I can run the 64bit apps. But no booting up into 64bit mode for me. That sucks. Well, only semi sucks but you know what I mean.
Snow Leopard and 64bit 32bit EFI Incompatibilities
To find out what version of the EFI you have on your Intel Mac you can do one of the two following things…
1. Open Terminal and type this command:
ioreg -l -p IODeviceTree | grep firmware-abi
That will the return the result 32bit EFI or 64bit EFI…
2. Download and run this app… Startup Mode Selector
This little app will tell you how compatible your Intel Mac is in regards to Snow Leopard and running it in 64bit mode.