Hello and thanks for your response. I have read up on using the 970 EVO Plus with the 2013 Mac Pro and how the firmware must be updated. That would be done by installing Catalina via a USB drive that is configured and formatted as a macOS install drive, correct? Or is there another method?
After connecting and configuring all drives on the AngelShark, I'm imagining I would have to do something like this - boot from a Catalina USB installer, then install Catalina to a 970 EVO Plus. Or, would I need to first install Catalina to the original Apple factory SSD, then do a second install to the 970 EVO Plus, then wipe the Apple factory SSD and put my Sierra build back on there?
Yes, before installing AngelShark you need to install Catalina/Mojave on your Apple OEM SSD, then do all the updates and you will need to reboot sometimes, with one of the reboots, the Mac Pro firmware will be updated automatically by Software Updates.
After you have the current BootROM, as today is 135.0.0.0.0, you can shutdown and install the AngelShark.
With AngelShark installed, you can install Catalina/Mojave directly to the SSD you want, no need to clone from the Apple OEM SSD.
After everything installed, you can wipe your Apple OEM SSD and install Sierra. For installing Sierra you will need to make an USB installer with createinstallmedia. You can't install a previous version of macOS from a newer version or use Internet Recovery, you need to boot from an USB installer.
Btw, this is the AngelShark thread:
Test Mac Pro Specifications MacPro6,1 BootROM: MP61.0120.B00 macOS High Sierra 10.13.1 (17B1003) E5-1660v2 3.7GHz (15MB L3) Hexacore 16GB of Apple/SKHynix PC3-14900 ECC Apple/Samsung SM0256G PCIe SSD (SSUBX based) 2x AMD FirePro D300 with 2GB VRAM Testing Tools for SSD Benchmarks AJA System...
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