2.5" SATA III SSD not seen in BIOS as a boot disk

The machine is MSI Titan GT80 SLI and it has 4 SSDs: 3x2280 PCIe and 1x2.5" SATA III SSD.

I have no issues with making images of the primary boot SSD, from one 2280 to another 2280 using Macrium Reflect. Then I use the bcdboot command to make the drive bootable.

however, I recently cloned the 2280 SSD from the primary boot drive to the 2.5" SATA III SSD. The cloning process went as usual (I used Macrium Reflect for years). then I did the usual bcdboot stuff. Once I rebooted, the 2.5" SATA III is not visible in BIOS under "boot" where the boot disks are visible. All the 2280s are visible, the PCIe ones.
the 2.5" is not visible and thus not selectable. However, it is visible under hardware section and it's certainly visible once the machine is up off the primary boot SSD. You can format it, clone to it, write data, etc. So the system sees it but it's just not recognized as a boot disk at all.

If you clone why do you then mess with it a correct c!one should boot ok

Josbeph said:

Have you tryed updating the BIOS?

The bios is latest and greatest.

Regardless of what's on the disk, the BIOS does not see it hardware wise when you go the boot section and you see the order in which disks can be moved up and down. You cannot chose it -- it's not there.

Yet the system sees it in all other ways. You can write data to it certainly and also it's visible in the hardware section. Just cannot be made a bootable disk.