Hello mate
Lets see if we can find a fix shall we.
Save your bios settings, either as a profile or write them down.
Clear CMOS and reboot to bios.
At defaults run through to OS with the new storage device fitted.
Is the device picked up?
If yes, rock and roll.
In no, then power down and label each of your connected hard drives with which SATA port they were fitted to. Remove all hard drives. Including the NVMe drive.
Clear CMOS again while powered down.
Fit the NVMe drive.
Power on and you should see the M2 drive picked up by the bios as it searches for the boot sector.
Let me know how it goes.
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