Question M.2 SSD detected in BIOS but not in Windows

[i7killpii]

Hi everyone. I'm running a system on ASUS Z790 Hero, and it just happened that one of M.2 SSDs now is not detected or shown in OS, though in BIOS it seems fine.

The MB features 3 M.2 slots and I have them all installed with NVMe SSDs. Tried swapping SSDs and found that the M.2 slot under CPU (M.2_1, CPU attached) is the problem. SSD installed in the slot is shown in BIOS but not in system, device manager or any 3rd party software etc. The system had run fine during past few weeks, and I did not have any major changes over it.

Any help will be appreciated.

Just FYI: M2_1 (shown in BIOS but not in system): Samsung 990 Pro 2Tb

M2_2: WD SN850 2Tb

M2_3: Samsung 980 Pro 2Tb



Edit: The disk controller is only visible from AIDA64 under PCI devices, as highlighted.

 

[gmikkonen]

Did you make it a volume? Partition?

 

[i7killpii]

Did you make it a volume? Partition?

Used to format as a single non-system partition for general purposes. However not able to do that right now, as it is not detected in device manager, diskpart cmd or anything else in Windows.