It seems I have "bricked" my 2009 MacPro 5.1 I tried to upgrade from Big Sur using OCLP to Monterey (I could not run the latest LR & PS) Now I cannot get the machine to boot. I made a bootable drive on a MacBookPro I also swapped my – non flashed – RX580 for a GTX 680 flashed to see if I could get into recovery. The system chimes but will not boot from the drive. If I remove the drive I get the folder with a ? which means it cannot find the OS. Ive done the usual resets several times but nothing. Any ideas? Thanks
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MP 1,1-5,1 No boot
- Thread starter petercorb
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Install a supported macOS release with another Mac. After that, remove all disks from your Mac Pro and install just the supported macOS disk and try to boot from it.
If you still can't boot, then power off, remove the PSU power cable from the mains, remove the RTC battery, connected the PSU to the mains and try to boot WITHOUT the RTC battery (this bypass the NVRAM volume). If you can boot now, you have a corrupt NVRAM and will need a BootROM reconstruction service.
If you still can't boot, then power off, remove the PSU power cable from the mains, remove the RTC battery, connected the PSU to the mains and try to boot WITHOUT the RTC battery (this bypass the NVRAM volume). If you can boot now, you have a corrupt NVRAM and will need a BootROM reconstruction service.
Tried your suggestion. Made a bootable USB of Big Sur, removed all peripheries, just the monitor. Starts with one chime, I get a light grey screen with a "no entry" sign – a circle with a diagonal line. Then the computer shuts down.
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No, you didn't ... Big Sur is not a "supported macOS release" on the problem unit.
I suppose it may have been supported on the unit you created the stick on, but what was meant was a macOS release supported on the problem unit (Mojave/Older)
OK so I had a bootable disk with Mojave installed. Did as suggested; computer started, chimed once. The grey screen appeared, this time no "no entry sign" but did not boot. Computer then shut down and restarted after approx 5 mins, now screen is black.
OK so I will make another bootable, not sure about this one as its been awhile I will then revert. Thanks
Wow. yes I made a new bootable Mojave, removed the RTC and it is now in MacOS utilities. What now ??
Seems you just confirmed that the BootROM is really corrupted - when you can only boot without the RTC battery, the EFI firmware completely bypass the NVRAM volume - this is a common occurrence with cross-flashed early-2009 Mac Pros. You can try to install Mojave to a spare disk and then you can get a BootROM reconstruction service.
Btw, when installing macOS to a Mac Pro without the RTC battery, my choice is always Mavericks since without SIP will make much easier to dump/flash the reconstructed BootROM image and 10.9.5 is still a OS X version that is not utterly dependent on the NVRAM.
OS X Mavericks Official Installer : Apple INC : Free Download, Borrow, and Streaming : Internet Archive
Official OS X Mavericks .app Installer from the Mac App Store.Un-archive the zip archive and you will get the app Installer. A bootable ISO or bootable USB can...
archive.org
I'll send you a PM about the BootROM reconstruction service required files, service fee and turnaround time.
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Thank you. I am in the UK is there a service here?You confirmed that the BootROM is corrupted, when you boot without the RTC battery the firmware completely bypass the NVRAM volume.
You can try to install Mojave to a spare disk and then you can get a BootROM reconstruction service. Btw, when installing macOS to a Mac Pro without the RTC, my choice is Mavericks since the SIP absence will make it easier to dump/flash the reconstructed BootROM image.
OS X Mavericks Official Installer : Apple INC : Free Download, Borrow, and Streaming : Internet Archive
Official OS X Mavericks .app Installer from the Mac App Store.Un-archive the zip archive and you will get the app Installer. A bootable ISO or bootable USB can...archive.org
I'll send you a PM about the BootROM reconstruction service required files, service fee and turnaround time.
You just dump the current BootROM image, get everything else required, upload it, then after the BootROM image is reconstructed, you flash back to your Mac Pro. No need to take your Mac Pro to a service center.
Please take a look at your PMs, top right corner of the site, click on the letter icon. I've already sent you a PM about the BootROM reconstruction service required files, service fee and turnaround time.