Last week I purchased a Mid 2012 Mac Pro 5.1
When I bought it it was Running Mojave, no Opencore, working perfectly.
2x 3.46Hz Six Core Xeons
64GB RAM
320GB HDD
2TB SSHD
1TB PCIe SSD
XFX Radeon HD7950 Double D with flashed Apple firmware
Worked perfectly, booting into Mojave natively, showing the Apple bootpicker just fine.
Having read up on Open Core, I decided I'd like to make this a dual boot system.
Created an OpenCore bootloader on the 320GB Drive, which is in Slot 1, created a Monterey installer on USB drive with OpenCore and installed Monterey without any fuss, booting fine via OpenCore, installed on the PCIe SSD, works a charm. Flawless.
Created Windows 11 installer with Rufus on a PC to remove the TPM checks etc
Booted off that via Open Core, attempted to install but kept getting error about "Unable to configure the drives for reboot" or similar, which I read was because the Windows installer gets confused about the other EFI partitions.
So I followed the guide to break out into a command prompt during install, use diskpart to edit the GUID of the other EFI partitions to standard volumes instead of system volumes, attempted to install again still got the same error.
So I obtained a 2TB SATA SSD, which I installed the Opencore bootloader onto
Rebooted the Mac with the 2TB SSD as the only drive in the machine, and used Opencore bootloader to start the Windows 11 installation from the Bootable USB, during install I allowed the Windows installer to erase all the partitions on the 2TB SSD
Installed fine, upon reboot I made sure to power down the Mac before it tried booting the Windows UEFI partition natively
Re-install the 320GB HDD in Slot 1 so that the Open Core bootloader on that drive was the first boot device it saw
Opencore boot loader loaded fine and allowed me to continue the windows installation from the 2TB SSD
Install completed successfully, however as soon as GPU drivers were installed, the display would go blank
I re-added the 1TB PCIe SSD, rebooted, and was able to boot back in to Monterey fine via Open Core
But any time I booted the Windows 11 drive via Open Core, Windows splash screen then blank screen
UEFI GOP I hear you say.
So I whipped out the GPU and put it in my Windows 11 desktop PC, booted fine, installed drivers fine, and was running in UEFI mode fine without any modifications.
I flashed the BIOS on the graphics card back to factory, found that the factory GPU BIOS didn't support UEFI GOP, so I used the GOP insertion tool to amend the factory firmware, reflashed it, rebooted in the PC to make sure it was all working well, everything was fine and dandy, so I put the card back in the Mac Pro
Mac Pro didn't display they grey screen any more on startup but did display Open Core bootloader fine. Attempted to boot in to Monterey, crashed during start up and powered off. Restarted the Mac, now it powers right off after the start up chime.
Took the card out and put it back in the PC, reflashed it back to the custom Mac firmware that was already on the card (I made sure to back it up before making any changes), rebooted the PC, still working fine, booting into Windows 11 without an issue.
Put the GPU back in the Mac, still I get as far as the start up chime then Mac powers itself off.
Attempted to do a PRAM reset but Mac powers itself off after 2nd start up chime.
Took the GPU back out boots fine in my Windows 11 PC, but the Mac Pro seems dead now, powers up, chimes, and powers down won't switch back on until you pull the power for a second.
I have a Pixlas mod and Radeon VII arriving tomorrow, I had hoped to run this in Windows 11 and Monterey as a dual boot system.
Oh - somewhere in amongst all of this I had also burned a DL-DVD of Windows 11 install to try installing it in non-UEFI mode, when booting from the DVD the Mac hangs on the windows splash screen.
And I've made sure never to let the Mac boot directly to a Windows 11 UEFI drive or installer - it's always been via Open Core - to avoid damage to the Apple firmware.
Not sure where to go now, other than to a corner to cry, and I'm fast running to hair to tear out
When I bought it it was Running Mojave, no Opencore, working perfectly.
2x 3.46Hz Six Core Xeons
64GB RAM
320GB HDD
2TB SSHD
1TB PCIe SSD
XFX Radeon HD7950 Double D with flashed Apple firmware
Worked perfectly, booting into Mojave natively, showing the Apple bootpicker just fine.
Having read up on Open Core, I decided I'd like to make this a dual boot system.
Created an OpenCore bootloader on the 320GB Drive, which is in Slot 1, created a Monterey installer on USB drive with OpenCore and installed Monterey without any fuss, booting fine via OpenCore, installed on the PCIe SSD, works a charm. Flawless.
Created Windows 11 installer with Rufus on a PC to remove the TPM checks etc
Booted off that via Open Core, attempted to install but kept getting error about "Unable to configure the drives for reboot" or similar, which I read was because the Windows installer gets confused about the other EFI partitions.
So I followed the guide to break out into a command prompt during install, use diskpart to edit the GUID of the other EFI partitions to standard volumes instead of system volumes, attempted to install again still got the same error.
So I obtained a 2TB SATA SSD, which I installed the Opencore bootloader onto
Rebooted the Mac with the 2TB SSD as the only drive in the machine, and used Opencore bootloader to start the Windows 11 installation from the Bootable USB, during install I allowed the Windows installer to erase all the partitions on the 2TB SSD
Installed fine, upon reboot I made sure to power down the Mac before it tried booting the Windows UEFI partition natively
Re-install the 320GB HDD in Slot 1 so that the Open Core bootloader on that drive was the first boot device it saw
Opencore boot loader loaded fine and allowed me to continue the windows installation from the 2TB SSD
Install completed successfully, however as soon as GPU drivers were installed, the display would go blank
I re-added the 1TB PCIe SSD, rebooted, and was able to boot back in to Monterey fine via Open Core
But any time I booted the Windows 11 drive via Open Core, Windows splash screen then blank screen
UEFI GOP I hear you say.
So I whipped out the GPU and put it in my Windows 11 desktop PC, booted fine, installed drivers fine, and was running in UEFI mode fine without any modifications.
I flashed the BIOS on the graphics card back to factory, found that the factory GPU BIOS didn't support UEFI GOP, so I used the GOP insertion tool to amend the factory firmware, reflashed it, rebooted in the PC to make sure it was all working well, everything was fine and dandy, so I put the card back in the Mac Pro
Mac Pro didn't display they grey screen any more on startup but did display Open Core bootloader fine. Attempted to boot in to Monterey, crashed during start up and powered off. Restarted the Mac, now it powers right off after the start up chime.
Took the card out and put it back in the PC, reflashed it back to the custom Mac firmware that was already on the card (I made sure to back it up before making any changes), rebooted the PC, still working fine, booting into Windows 11 without an issue.
Put the GPU back in the Mac, still I get as far as the start up chime then Mac powers itself off.
Attempted to do a PRAM reset but Mac powers itself off after 2nd start up chime.
Took the GPU back out boots fine in my Windows 11 PC, but the Mac Pro seems dead now, powers up, chimes, and powers down won't switch back on until you pull the power for a second.
I have a Pixlas mod and Radeon VII arriving tomorrow, I had hoped to run this in Windows 11 and Monterey as a dual boot system.
Oh - somewhere in amongst all of this I had also burned a DL-DVD of Windows 11 install to try installing it in non-UEFI mode, when booting from the DVD the Mac hangs on the windows splash screen.
And I've made sure never to let the Mac boot directly to a Windows 11 UEFI drive or installer - it's always been via Open Core - to avoid damage to the Apple firmware.
Not sure where to go now, other than to a corner to cry, and I'm fast running to hair to tear out
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