In my case it is not detected in the bios.

After multiple reboot from bios, the SSD (980 PRO) is detected and windows is loaded.
When I connect a second NVME SSD (970 EVO) at M2_B slot (backside) connected via B550 chip, system is freezing randomly in windows.

The backside...

Issue is still occurring wit F13a bios, second m.2 ssd connected to the backside slot with PCIe 3.0 is detected.
But the Samsung 980 pro at front slot is not detected anymore.
?

L!ME what was the name of the old riser card and of the new one?

Thx

I had the same issue with F12 version and Samsung 980 Pro.
It occurred only once, but i already updated to F13a.