OpenCore Legacy Patcher: Success on MP 5,1... with small issues

[The Green Ray]

I’ve run into a problem with my ancillary drives — an internal Samsung EVO SSD SATA and (initially) external Crucial M2 NVMe in a PCIe slot.
I thought I could just dupe the Crucial drive in a USB 3 enclosure, then move it to the PCIe card. (The one that’s in and working is 500GB, the new one is 1TB.)
In the Startup Disk selector in Settings, both extra drives turn up as boot alternatives, but when I select them, I get an error message: ""Unable to set startup disc. An error occurred while setting [my SATA SSD] as startup disc. The operation couldn't be completed (SDError Domain error 104."
The fix apparently lies in Recovery Mode>Utilities>Startup Security Utility, where you can turn off the protections that block the disc from booting. When I got into Recovery, though, and clicked on the drop-down, the SSU produced an error message saying the the firmware wasn’t supported.
Now, the up-to-date firmware was, I’m sure, installed as part of the Monterey installation. Today I’ve been going around in rebooting circles, trying this, trying that. Nothing is working, which leaves me without a bootable second drive, and useless 1TB SSD.

 

[MacHosehead]

Now, the up-to-date firmware was, I’m sure, installed as part of the Monterey installation.

It is my understanding that the last firmware update for the MP5,1 comes with the installation of Mojave and has NVMe support. Here is a thread concerning this:
https://forums.macrumors.com/threads/macpro5-1-bootrom-thread-144-0-0-0-0.2132317/

 

[The Green Ray]

Thanks, MHH! In the interim I've managed to get the SATA SSD working with Monterey, booting as it should. Did this by going through the whole OpenCore routine from scratch for that drive. I plan to attempt the same soup to nuts routine with another PCIe drive next week. The OCLP'd drive doesn't seem to want to boot from my main SSD startup if it's in a USB 3.0 enclosure, but will with no problem at all from its PCIe slot. A mystery, as these hacks always are.

 

[The Green Ray]

P.S. I also used these terminal commands on the SATA drive before building the OCLP on it: Find the correct EFI: "diskutil list", then hit Enter. Then: "diskutil mount /dev/disk[your identifier]", then Enter. Then: "bless -mount /Volumes/EFI/ setBoot", then hit Enter. Close Terminal, restart your Mac. This should get you back to the Recovery screen.

 

[GreenAcresFilms]

Ugh! Ran into terrible trouble tonight. After a few blissful days of using Monterey I restarted from my internal SATA ssd (from my PCIe ssd). I had downloaded 12.6 on the PCIe drive, but not sure if this is where the trouble started. On the reboot I couldn’t get past the boot picker screen except to Recovery… which I did and installed a TM backup. Still in the endless boot loop. I get a chime, the boot picker screen and if I pick the SATA drive I get the Apple logo and briefly a progress bar then quickly a black screen, then back to a restart. Can my MP be recovered? (You might see this same post posted “by” my wife, Lisa Mary. I’m on her iPad and wasn’t sure I could get through to my account, so, apologies for the unnecessary duplication.)