[SOLVED] NVMe SSD with Win10 (using PCIe adapter) not shown in BIOS, yet shown in Disk Manager

[Maru777]

Build:
https://pcpartpicker.com/list/FPkQFt
SSD added:
https://www.amazon.com/gp/product/B07M7Q21N7/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1
M.2 to PCIe adapter:
https://www.amazon.com/gp/product/B075MDH28Y/ref=ppx_yo_dt_b_asin_title_o01_s00?ie=UTF8&psc=1

Issue:
Installed SAMSUNG 970 EVO Plus 500GB NVMe M.2 SSD into my LGA 1150 (May 2013) motherboard's second PCIe x16 slot using "M.2 NVMe to PCIe 3.0 Host Controller Expansion Card" adapter (which does supports the 2280 standard).
BIOS set to LEGACY+UEFI.
Win10 is already installed on internal HDD.
Saw SSD was not displayed in BIOS, but did show up in Win10 Disk Manager. Initialized SSD as GPT.
Installed SAMSUNG SSD driver, restarted computer.
"Re-set/clean installed" Win10 on HDD, and restarted.
Downloaded SAMSUNG Data Migration tool, and "migrated/cloned" full contents of Win10 from HDD to NVMe SSD. Restarted.
BIOS still doesn't show SSD.
Updated BIOS to latest version (1.9). Restarted.
BIOS still doesn't show SSD.
Disk Manager however shows SSD as "healthy" NTFS formatted copy of my original Win10 HDD.
Tried booting SSD with no other storage medias connected. BIOS displayed EFI Shell and said "map: Cannot find required map name." and throws me into Shell.

Is the motherboard too old to support NVMe SSDs? Can a system boot from PCIe x16 using that adapter, or does it need dedicated on-board M.2 slot? Did I do something wrong?
Goal is to boot Win10 from SSD.
Help me, TomsHardware, you're my only hope.

Thanks!

 

[rgd1101]

motherboard too old.

 

[USAFRet]

Board is too old to support booting from that drive in a slot adapter.
It is OK as a secondary drive.

 

[Maru777]

Thank you for the quick replies!

 

[ban.codrut]

If you are a bit tech savy there are ways to add NVMe support into mb bios if OEM didn't release an update themselves.
Here is a nice well written guide on how the process of adding the EFI module to you BIOS.bin file