Chosen Solution
Hi My MacBook Pro stopped working awhile ago with the question mark at boot. I tried doing a Internet recovery but couldn’t see the PCIe SSD, so I thought the disk was dead, I have bought a new “Aura Pro X” and booted up internet recovery again, but it is still not seeing the disk :-( I then tried attaching a external disk and installed Big Sur on that and it is working without any problem, suddenly I could see my new PCIe SSD in Disk Utilities, so I installed Big Sur on that and finally it was working. I used it all day, but the next day it wouldn’t start again and couldn’t see the PCIe SSD, did the same thing again with the USB disk and again after sometime and several reboots the disk showed up, and worked for about a day before it did it again, Could this be my logic board that has failed??
I think you have two issues which makes this a bit more confusing! First the OWC Aura SSD requires your system is running High Sierra or newer as the system’s firmware needs to be updated so the newer macOS file system is recognized (APFS vs HFS+). To add to it the OS also offers a newer PCIe driver which the OWC SSD needs. Thats why you had issues seeing it as you where likely using Sierra or older macOS which doesn’t have the needed driver and if you had set it up using the external drive then you have a issue of which macOS is running your original or the newer! So lets open up System Preferences > Startup Disks I think you’ll find your external drive which is running Big Sur is the startup disk and while you had intended to install Big Sur on the internet drive for some reason it’s running Sierra or older!
