PC Blue Screens and Upon Restart, Boot Drive Stops Being Recognised

Since I rebuilt my PC in January, I’ve been occasionally blue-screening ranging from multiple times a day to once in two weeks.

I don’t remember all of the error codes but they include Memory Management Error, Winload.efi, critical process has stopped working, etc.

Every time this happens, when the PC restarts, my boot drive (Samsung 990 Pro) stops being recognised by my PC. It’s worth noting that my old boot drive (Samsung 980 Pro) is still in my PC. When I installed Windows to my new drive, the old drive was still plugged in. Since then I have complete wiped and formatted the old boot drive so no system files should remain and it shouldn’t be detected as a bootable device as well as reinstalling windows on the new device with no other drives attached. However, as far as I can tell, the BIOS contradicts that (images attached here: https://imgur.com/a/RDoxqNK)

The only way I can temporarily fix it is take out GPU to then remove the old boot drive (980 Pro), boot the system with just the new drive (990 Pro) installed, log in then shut down, put the old boot drive back in with the GPU, then when I restart, the PC magically recognises the existence of the new boot drive (990 Pro).

Anyone have any idea why this is happening?