Downgrading New Mac pro to Mountain Lion

aussie_geek

macrumors 65816
Original poster
Apr 19, 2004
1,093
0
Sydney Australia
Is it possible to downgrade a New Mac Pro to Mountain Lion?

Apple has removed the Open Transport API from Mavericks and we need it to run a specific medical program.

The software runs on our old Macs. Just wondering if its ok to do this on the new Mac Pro.


aussie_geek
 

Chundles

macrumors G4
Jul 4, 2005
11,981
364
Pretty sure you can only run the version of the OS that shipped on the machine or later.

Earlier versions, particularly whole number ones like 10.9 -> 10.8 don't have the drivers required to run the hardware.
 

Dark Dragoon

macrumors 6502a
Jul 28, 2006
843
3
UK
Would an alternative option be to run Mountain Lion in a virtual machine for that specific piece of software?
 

aussie_geek

macrumors 65816
Original poster
Apr 19, 2004
1,093
0
Sydney Australia
Thanks for the thoughts people.

I didn't think it could be possible.

We have a solution - albeit a messy one.

The software component that is incompatible is a DICOM server (medical image server). The actual viewing software used to manipulate the image is compatible - just the image import component is not.

Putting it simply we will set up some folder aliases over the network so the viewing software will just use the image folders on the old Mac as their repository.

We have also contacted the developers to get them to update their software! As technically, it is not compatible with Mac...


aussie_geek.
 
Last edited:

chevalier433

macrumors 6502a
Mar 30, 2011
510
13
Is it possible to downgrade a New Mac Pro to Mountain Lion?

Apple has removed the Open Transport API from Mavericks and we need it to run a specific medical program.

The software runs on our old Macs. Just wondering if its ok to do this on the new Mac Pro.


aussie_geek
Yes is possible put mountain lion installer in usb drive,startup with it,format your mac pro drive and install mountain lion on it.Instructions in google.
 

Dark Dragoon

macrumors 6502a
Jul 28, 2006
843
3
UK
Yes is possible install mountain lion in usb disk startup with it format your mac pro drive and install it.Instructions in google.
Interesting, have you experienced any driver issues when doing this?
I guess you had to at-least modify the installablemachines.plist and OSInstall.mpkg to get it to install.

I'm surprised this worked though.
 

chrfr

macrumors G3
Jul 11, 2009
8,193
2,523
Yes is possible put mountain lion installer in usb drive,startup with it,format your mac pro drive and install mountain lion on it.Instructions in google.
No, it will not work. You can't run anything but the builds of OS X specific to the new Mac Pro on them. Not even the App Store version of Mavericks works.
 

Dark Dragoon

macrumors 6502a
Jul 28, 2006
843
3
UK
None of those links appear to be of any use for running Mountain Lion on a new Mac Pro.

They seem to only link to sites explaining how to make a standard Mountain Lion installer which can be used with compatible Macs,
the new Mac Pro is not compatible with Mountain Lion, as it can only run a special build of Mavericks 10.9.1, or higher once newer versions of Mavericks is released.

This is the same with almost all Macs. They can only run the OS they originally came with or newer, not an older version.
 

Dark Dragoon

macrumors 6502a
Jul 28, 2006
843
3
UK
Err... sure, you can install a newer version of OS X on an older Mac, and indeed I've installed Mavericks on my original unsupported Mac Pro 1,1, as luckily the newer versions of OS X contain the drivers needed to run the older hardware.

However this is the exact opposite of running an older version of OS X on a newer Mac, where the older versions of OS X do not contain the drivers needed to run the newer hardware.
 

mikecwest

macrumors 6502a
Jul 7, 2013
978
326
I don't have a MacPro to test or try it on.

I am curious though, hopefully it won't violate any TOS here, but if people are able to install various forms of OSX on non-apple machines, wouldn't it theoretically be possible to install it in the same manner?

I am not asking anyone to give specific directions on how people install it on non-apple machines. I am asking the opposite, I am asking if anyone can explain why an apple branded "unsupported" machine would be impossible.

I believe that the limitation may be artificial, in the respect that the installer will query the machine, then deny based upon it's response. Its been many many years of Apple use for me (27 years), but i vaguely recall sometime in the past "tricking" a mac into letting me install older software for some reason.
 

chrfr

macrumors G3
Jul 11, 2009
8,193
2,523
I vaguely recall sometime in the past "tricking" a mac into letting me install older software for some reason.
This only works if it's a model of Mac that originally shipped with an earlier version of the OS. For instance, the mid 2012 Macbook Pros and Airs shipped with 10.7.4 originally, but eventually switched over and then shipped with 10.8.
On those machines, yes, you can reinstall 10.7.4 or 10.7.5. As with the Macbook Air and Pro, the Mac Pro will not run with an earlier version of the operating system than was available when it was released. As the others here have said, 10.8.5 does not have the required hardware support to boot it. Doesn't matter if you're trying to use a preinstalled copy of the operating system on another disk or trying to install, but it won't work either way.
 

MacDaddi

macrumors member
Oct 29, 2007
34
6
San Francisco
Yes is possible put mountain lion installer in usb drive,startup with it,format your mac pro drive and install mountain lion on it.Instructions in google.
It's not possible if the hardware is 2014ish and above as Mountain Lion does not have the correct drivers to support the new hardware.