I just replaced my motherboard with an MSI B450M Mortar Max because of random freezes with the old board (ASRock AB350M Pro4).
I reused all other parts:
Ryzen 5 1600
2x 8GB G.Skill RipJaws V 3200
Sapphire RX 560
Now when I boot into BIOS it detects the RAM correctly in the right slot (2x8 G.Skill), but it still says total physical DRAM memory is 8GB. Booting into Linux yields the same result, it only detects 8 GB.
I already tried booting with only one of either of the two and both booted and were detected as 8GB. I also swapped the sticks and it booted with only 8GB physical memory being detected.
Trying to boot with only one stick in one of the B slots resulted in no boot, but I guess thats just by design?
Unfortunately, while replacing, I dropped the CPU and some pins bent lightly. I readjusted them with a razor blade and it went in the new socket without a problem (it sits flush on all edges).
Now I don’t really now if it’s a defect motherboard, a defect CPU or incompatible RAM that causes the problem.