Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.

drnebulous

macrumors regular
Original poster
Apr 27, 2014
181
0
Salford, UK
I have had enough of Yosemite (incompatibility issues, stability issues, slow speeds etc...) so I want to go to Snow Leopard. The problem is, is that snow leopard isn't supported on my 2012 Mac Pro (3.2Ghz). I know that the 2010 mac pro is identical to the 2012, and that a lot of people with 2010 mac pros upgrade the firmware to 2012. I want to do the reverse so Snow Leopard will be compatible. So, how would I downgrade the firmware of my 2012 Mac Pro to 2010?
 
Even with the stock 2012 firmware?

As the previous post stated, it's the same 5,1 firmware for both 2012 and 2010 MP models. The main difference, other than CPU options, is that for the 2010 models, Apple provided a DVD install disc for OS X 10.6.4 while the 2012 models only got direct download. The problem with Snow Leopard is that it supports very few video cards, such as AMD 5770/5870 and older models. If you are using the AMD 5770/5870, you have to install with OS X 10.6.4 or later version as explained here.
 
I have had enough of Yosemite (incompatibility issues, stability issues, slow speeds etc...) so I want to go to Snow Leopard. The problem is, is that snow leopard isn't supported on my 2012 Mac Pro (3.2Ghz). I know that the 2010 mac pro is identical to the 2012, and that a lot of people with 2010 mac pros upgrade the firmware to 2012. I want to do the reverse so Snow Leopard will be compatible. So, how would I downgrade the firmware of my 2012 Mac Pro to 2010?

I can run snow leopard on my real 2012 but I can't install it. The trick is to use an existing installation (a clone drive) and the 2012 will boot it just fine. I used my 2009 iMac to make an external snow leopard drive and just put that in the 2012.
 
The main difference, other than CPU options, is that for the 2010 models, Apple provided a DVD install disc for OS X 10.6.4 while the 2012 models only got direct download.

Not totally true. The late 2010 models did not come with a DVD install disc. AMHIK.

Lou
 
The late 2010 models did not come with a DVD install disc.
I totally understand what you mean. The OS X Lion wasn't officially released until July 2011 while Mac Pro Mid 2010 model was first introduced in August 2010. Before OS X Lion was released, the 2010 MP came with a DVD install disc (actually two discs), but after July 2011, MP models did not come with DVD discs simply because Apple changed its distribution method of OS X. It's common practice that Apple includes the current version of OS X with the Mac. If your 2010 MP was produced after July 2011, yes it did not have install discs. Sorry I did not make it so precise earlier.
 
I can run snow leopard on my real 2012 but I can't install it. The trick is to use an existing installation (a clone drive) and the 2012 will boot it just fine. I used my 2009 iMac to make an external snow leopard drive and just put that in the 2012.

Correct. And no need to downgrade the firmware of the Mac Pro.
 
They're the same machine. A Snow Leopard disc will work in one without a problem.

Nope you are incorrect. I have tested this. Snow leopard will fail on a 2012. It will do nothing but crash. I specifically went and purchased a 2010 and slapped in 2 3.06ghz 6-core xeons in it and its awesome. I had to send back 2 x 2012 mac pros just for this reason alone until I figured it out.

The problem is that the firmware on an 2010 will be upgraded when you install 10.7. You have to watch out as there is a download that pops up for it. DON'T install it if you want to ever go back to snow. The firmware is changed to protect the EFI from virus and snow does not support this so it will wig out.
 
According to Apple the latest firmware for the Mac Pro 2010 (-2012) is MP51.007F.B03 (EFI 1.5): http://support.apple.com/de-ch/HT201518

I have the same firmware on my Mac Pro 4,1 -> 5,1 (MP51.007F.B03), and Snow Leopard 10.6.8 runs fine (except for graphics acceleration, the GTX 680 is not supported).

Are you sure that there exists a newer firmware?
 
Even with the stock 2012 firmware? On everymac, it says that 10.7.4 is the lowest the 2012 mac pros can do?

I have a 2012 5,1 Mac Pro and Snow Leopard 10.6.8 runs and boots fine. The 2012 Mac Pro originally came with Mountain Lion 10.8.2 installed. No other OS install DVD was included. The Snow Leopard bootable drives came from a 2010 Mac Pro and the other from a 2009 Mac Pro. I have not tried installing Snow Leopard directly to the 2012 Mac Pro using the retail 10.6.3 installer so I could not comment on that.

I am using 2 OSXs alternately, Snow Leopard and Mountain Lion 10.8.3. I tried Mavericks but I shifted back to Snow Leopard/Mountain Lion.
 
Nope you are incorrect. I have tested this. Snow leopard will fail on a 2012. It will do nothing but crash. I specifically went and purchased a 2010 and slapped in 2 3.06ghz 6-core xeons in it and its awesome. I had to send back 2 x 2012 mac pros just for this reason alone until I figured it out.

The problem is that the firmware on an 2010 will be upgraded when you install 10.7. You have to watch out as there is a download that pops up for it. DON'T install it if you want to ever go back to snow. The firmware is changed to protect the EFI from virus and snow does not support this so it will wig out.

The MacPro5,1 did not get an EFI update in 10.10.2 to protect it from malware. Only the MacPro6,1 did. Snow Leopard does correctly run on a fully updated 2012 Mac Pro without complaining. If your machine crashed, then it was either misconfiguration or contained incompatible hardware. Many others, as well as myself, dual boot between Snow Leopard and 10.9/10.10 on a 2012 Mac Pro all without problems. Macsonic, the poster above this post, is running such a configuration.
 
I am grateful for this thread. Most other places lead me to believe Snow Leopard could not be installed on 2012 MP hardware.

To summarize and confirm just to make sure I am understanding correctly: A Mid-2012 Mac Pro 5,1 running 10.10.4 Yosemite can be downgraded to Snow Leopard without anything fancy needing to be performed?

Intending to use the retail 10.6.3 Snow Leopard disc. Please tell me if that works.
 
Last edited:
I have had enough of Yosemite (incompatibility issues, stability issues, slow speeds etc...) so I want to go to Snow Leopard. The problem is, is that snow leopard isn't supported on my 2012 Mac Pro (3.2Ghz). I know that the 2010 mac pro is identical to the 2012, and that a lot of people with 2010 mac pros upgrade the firmware to 2012. I want to do the reverse so Snow Leopard will be compatible. So, how would I downgrade the firmware of my 2012 Mac Pro to 2010?
Check the graphics card option.Some of the latest cards are not supported. However, in my experience the ATI HD 5870 did work.
 
Intending to use the retail 10.6.3 Snow Leopard disc. Please tell me if that works.
This will not work. You need the 10.6.4 disc from a 2010 Mac Pro, or an already installed copy of 10.6.5 or later.
 
As others have said...

The 2012 Mac Pro will RUN snow leopard, but it will not let you install. No version of 10.6.X ever sold on a disc will work because they do not have drivers for the graphics card (and there is probably a plist file with a list of supported models in the installer). 10.6.4 was the first version to have the needed drivers, but no disc was ever sold with that version (or later).

The easiest work around is to install 10.6.X on a machine that allows it, upgrade the drive to 10.6.8, and then put that drive in the Mac Pro.
You can also use target disk mode on the MP and run the install from another Mac.
In theory, you could also install a supported graphics card, uncompress the installer, modify the plist file, recompress the installer, install 10.6.3, upgrade to 10.6.8, re-install the graphics card.
I have not tested the 3rd option, so I do not recommend it.
 
Thanks for the thorough replies.

So any SL 10.6.4 install disc will work then? The workarounds that minifridge detailed aren't necessary as long as you run the 10.6.4 install disc that came with 2010 hardware?

I noticed that Ebay auction comes with an 80 GB hard drive, is there any reason for that, or is it just a bonus item for the auction?
 
Last edited:
^^^^The seller states:

ebay rules reacquire you bundle restore discs with original hard drive/hardware. HD is functional, was removed from a Mac.

Don't know if I believe that or not, but who knows?

And Yes to your first question.

Lou
 
Okay, just making sure it wasn't required for downgrading. I am sure in passing I saw some auctions with just the install disc which are bound to be cheaper, but even if that's not the case, it's worth it for 10.6 on the best pre-bucket MP!
 
Thanks for the thorough replies.

So any SL 10.6.4 install disc will work then?
No, only one from the Mac Pro will work. If it's a 10.6.4 disc from a Mac Pro, it'll work because that was only for the 2010+

I noticed that Ebay auction comes with an 80 GB hard drive, is there any reason for that, or is it just a bonus item for the auction?
The seller's explanation makes no sense as the Mac Pro was never sold with an 80GB disk. I suspect this is just their interpretation of some eBay "rule."
 
I have had enough of Yosemite (incompatibility issues, stability issues, slow speeds etc...) so I want to go to Snow Leopard. The problem is, is that snow leopard isn't supported on my 2012 Mac Pro (3.2Ghz). I know that the 2010 mac pro is identical to the 2012, and that a lot of people with 2010 mac pros upgrade the firmware to 2012. I want to do the reverse so Snow Leopard will be compatible. So, how would I downgrade the firmware of my 2012 Mac Pro to 2010?

Here you go. This set is only $20 and he's got a few sets available.
 
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.