Yosemite 10.10.5 & 64-bit processing

[Mike G R]

How do I confirm that my MacPro3,1 (early 2008) is using a 64-bit kernel?

Here's what I know:

- Activity Monitor states in Kernel task is 64.
- Preference Panes in 'About this Mac' state:
64-bit (intel): Yes
- I used
"sudo systemsetup -setkernelbootarchitecture x86 64"

Apple says that 2008 MacPro shipped with 64bit ability but that it does not boot by default into 64bit.

Mike G R

 

[harryb2448]

All Mac Pros 3.1 are 64bit architecture. The fact you are running Yosemite confirms this. Mac Pros model 1.1 and 2.1 whilst having 64bit archictecture, were limited for some reason to 32bit EFI. To activate the 64bit kernel have a read of this link with several suggestions. Note the improvements for photographers. Just enjoy Mike knowing your model does not have the handicap of 32bit EFI.

I would suggest at least downloading El Capitan OS X.11 and making an 8GB USB thumb drive installer even if you don't use it for now. DiskmakerX is an easy to follow method of making the bootable thumb drive. From early reports El Capitan is the final operating system for your Mac Pro. mac osSierra is going to require a 2010 Mac Pro.


http://macperformanceguide.com/SnowLeopard-64bit.html

 

[Mike G R]

Hello Harry,

What is the advantage of 64-bit EFI if the OS still won't recognize/allow a 64bit kernel?
I looked at the article you suggested and tried a few things:
"The Pram Method" does not work.
The 'Two finger dance' does't work.
I looked at the following file "/Library/Preferences/SystemConfiguration/com.apple.Boot.plist" and it looks similar to the example.