GUIDE How to Install macOS Big Sur on Unsupported Mac Pro [MacPro3,1, Mac Pro4,1 and MacPro5,1]

[EliteMacx86]

Yes the USB was made on the target Mac. The screen is completely black initially, then the normal login window appears.

Okay. Can you provide the video/screenshot when pressing Option key during restart?

 

[jimbo]

Hi thanks for your help and apologies with the delay - the update took out my wifi, so i've just upgraded the card.
I managed the update with another method and its future-proofed now for mac updates. Happy to share the OC and bundled folders if you like.

 

[EliteMacx86]

Hi thanks for your help and apologies with the delay - the update took out my wifi, so i've just upgraded the card.
I managed the update with another method and its future-proofed now for mac updates. Happy to share the OC and bundled folders if you like.

That's great. If you want, you can add it to the thread.

 

[jimbo]

You can download the OC folder here containing everything you need to update to Catalina or Big Sur.
https://mega.nz/file/Q84GEYDT#MEPOuNV7M2nZpNmiL63BYVEAcQoOvrzO9yl7Sko0znA

This method works on Mac Pro 5 1 and i'm told it will work with most unsupported Macs.

The steps are quite simple to follow...

1. Open OC app. Go to Menu > Tools > Mount EFI
Here you need to mount the EFI partition from your boot drive.

2. Delete the contents of the mounted EFI and replace with either SINGLE SOCKET or DUAL SOCKET 'STANDARD' folder contents (depending on your system). Im on a Mac Pro 5 1 - so I used the DUAL SOCKET / STANDARD folder contents.

3. Copy the 'Bless Opencore' to the same EFI folder and then run the app.

4. Reboot your Mac, selecting your normal boot drive at the boot loader screen.

5. Once restarted, go to System Prefs > Software Update and you should see Catalina or Big Sur option to install, depending on what system you're on. Download required installer and then begin install process as you would with a supported Mac.

6. When the installation has completed, open OC app again and mount the EFI boot partition. Delete the EFI folder and replace with the contents of the respective GPU ACCELLERATION folder, then restart your Mac.

7. If you want to run MacOS software updates in future, you need to go back to Step 2 and replace the contents with the STANDARD folder and post-update repeat Step 6.

Hope this helps someone!

 

[dmarinescu]

bricked my mac pro (a 7 years old $10000 machine) thank you very much. have a nice life

 

[EliteMacx86]

bricked my mac pro (a 7 years old $10000 machine) thank you very much. have a nice life

xD

 

[UlliQ]

The requirments demand bot rom version 144.0.0.0.0 but I have an unpatched MacPro3,1 with boot rom version MP31.006C.B05 which is not able to boot from APFS natively. Is it possible to install BigSur anyway using this guide? I currently use Refind to boot my DosDude1 Catalina installation with RX 580 graphics card.. Open Core (https://forums.macrumors.com/thread...n.2180095/page-53?post=28255048#post-28255048) also works fine.

 

[EliteMacx86]

The requirments demand bot rom version 144.0.0.0.0 but I have an unpatched MacPro3,1 with boot rom version MP31.006C.B05 which is not able to boot from APFS natively. Is it possible to install BigSur anyway using this guide? I currently use Refind to boot my DosDude1 Catalina installation with RX 580 graphics card.. Open Core (https://forums.macrumors.com/thread...n.2180095/page-53?post=28255048#post-28255048) also works fine.

Yes, you can install it by following the guide. OC is required for HW acceleration, native updates and TB support.

 

[markerobjr]

Hello, So i ahve followed this guide to the letter and i can't seem to get it installed. I get hte DO NOT ENTER graphic. and a black screen with some text that comes up before booting. any idea? I can get a picture of the text if you want. I just hope I didn't brick my machine.

also is it possible to boot back to the previous OS if I didn't erace the main drive?

 

[EliteMacx86]

Hello, So i ahve followed this guide to the letter and i can't seem to get it installed. I get hte DO NOT ENTER graphic. and a black screen with some text that comes up before booting. any idea? I can get a picture of the text if you want. I just hope I didn't brick my machine.

also is it possible to boot back to the previous OS if I didn't erace the main drive?

With Catalina, your Boot ROM was not updated?