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macrumors 6502a
Original poster
Aug 8, 2006
As 2009 mac pro (4,1) can flash to be 2010-2012 (5,1).

And it hasn't different to the other two.

Now, apple state that, macOS Sierra has support only 2010 Mac Pro and later.

So now there are two option for macOS installer to handle 2009 Mac Pro which flash to 5,1.

1 Define it as 5,1 mac pro and let the installer act like 5,1 mac pro
2 Define it as early 2009 mac pro and block the installer.

Do you guy think what is the way apple choose?

PowerMac G4 MDD

macrumors 68000
It's gonna be odd seeing all of these 4,1s being flashed to 5,1, even without CPU upgrades - because, that's actually possible. If I do it, I may just upgrade the CPUs. I'd feel lame flashing to 5,1 and not doing anything. Granted, I'd rather not have the added stress on my power supply, as I'd like to save its juice for future GPUs.
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macrumors member
Jul 3, 2014
Apple is probably adding an artificial limit that has little to do with the acutal ability of the computers to run the OS.

I understand the MBA 2008 but why the Mac Pro 3,1 or 4,1 would be unable to run the OS but a 2010 Macbook (not even pro) is.....
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macrumors 6502
Mar 4, 2016
Bald Knob Arkansas
I'm with you same with the 1,1 and 2,1 pro they could of released a 64bit firmware and solved it right then and there. so i just hope they do it right and people can get it running on the 4,1 3,1 2,1 and my 1,1
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macrumors member
Jan 15, 2015
I expect Sierra to run on all cMP (1,1 & 2,1 with sfott or other tools), with the limitation being video card capabilities. The blurb about only supported on 2010 and up is likely just a cover for the people who still have original 2600xt and gt120s.


macrumors G4
Mar 10, 2009
Apple is probably adding an artificial limit that has little to do with the acutal ability of the computers to run the OS.

1. The 4,1 is now on Apple's Vintage and Obsolete list. ( Apple isn't alone here. Go look for active development on new drivers for 7-9 old GPU add in cards. )

2. The configuration of 4,1 that they are dropping based on the standard, sold at the time, components ( 2008 era GPUs, etc. ). So not only obsolete hardware but higher percentage of folks who still have it production service are now off of the standard configs. An even more deeply motivated business case for not doing this for free ( how much are folks paying for macOS 12 ? $0.0. Which is $0.0 that goes into paying for the work to get done. )


macrumors 65816
Feb 26, 2014
What's the appeal of Mavericks? As far as I know, Mavericks suffered from GPU driver issues.,8206.0.html

I have absolutely zero issue with Mavericks (using an "Apple 5770"). Like I said in other threads, I'm working mainly with Pro Tools, which has some serious graphic issues in El Capitan. In Mavericks they're gone, + less bg tasks, + less cpu demanding, + Lucida Grande (which is still a much better option on non-retina screens).

I'm not saying that I won't upgrade, but that's certainly not a priority for now. I can reinstall El Capitan on my two MPs if I need it and it does work fine - but I'm still more comfortable with the 10.9 UI. btw I have nothing against change. It's just that 10.9.5 works better for me right now.

As for Sierra...meh.


Jun 3, 2015
Anyway, I assume we can know the answer in few hours. My understanding is if any developer can install the Beta 1 on a 2009 flashed 5,1 cMP. Then I can safely assume we can do the same thing with the official release later.
Hopefully it works. That's why I like cMP... There's usually workaround....
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macrumors member
Jun 11, 2016
"Not supported" doesn't necessarily mean that they will block it. It just means they won't provide support for it.

However, they have in the past blocked hardware with whitelists, so we'll see.

OK, so here is a brief update.

I have a Mac Pro 3,1. It won't even let me download the Beta saying "This version of OS X 10.12 cannot be installed on this computer." So you can bet your bottom dollar it is blocked :)
[doublepost=1465858308][/doublepost]Good news for you 4,1 folks... it works!!!
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