If you are using the original nVidia 7300GT, you will have to use a more modern graphics card that the Chameleon bootloader can understand. This can probably be fixed with some additional work, and maybe someone else can suggest some settings to accomplish this, but right now, with this guide, you can boot the 2007 Mac Pro (of course my 2006 has been upgraded to 2007) in 64 bit kernel mode, and the system works 100%, with sleep, shutdown, networking, CPU identification working properly. I did successfully accomplish this, and I can say that it works very well, with the only thing not recognized and working is the built-in audio. There's been some posts on this forum, as well as some earlier posts by netkas on the subject, about using the Chameleon bootloader to load the OS, since in theory, this should be a pretty darn compatible hackintosh! I attempted to configure the system to boot in this manner, using all of the information available in these posts, but all of the information and suggestions available are close, but none of them get everything right.

This is of course an arbitrary decision on Apple's part, as the Xeon CPUs in all the Mac Pros are certainly 64 bit capable.

As you probably know, these Macs have a 32 bit EFI implementation, so the Mac OS can only boot the 32 bit kernel.

I started doing some research on booting the 64 bit kernel on the 2006/2007 Mac Pro. I'm also a big hackintosh fan, and I've built numerous platforms going back to 2006, when it all began. After writing the firmware tools for these systems, I started to feel like the 2006 Mac Pro didn't get much of a boost from the 2007 firmware upgrade, unlike the 2009 upgrade, which unlocked a lot of potential. I'm a big Mac Pro fan, and I own both a 20 Mac Pro.

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