Is that memory on the QVL? There have been some articles written about the Ryzen memory controller, AGESA and UEFI recently... and the problems it still has. It is recommended to use QVL RAM until they are ironed out.
Go to the last page of this article and scroll down to "Ryzen RAM Compatibility" for more detail.https://www.hardocp.com/article/2017/04/11/amd_ryzen_5_1600_1400_cpu_review/5
The memory, F4-3200C16D-16GTZB
, is not on the support list for the Tomahawk B350.
The DDR speed can get to a maximum speed of 2933 MHz before it is incapable of starting. The memory is designed for an intel chip so I believe this is the issue.
I have the same ram, the RGB version though, running at 3200mhz on an MSI B350m Mortar, the Tomahawk's little brother, and the problem ive found with that CL16 RAM, is they use 2 different types of chips on it, its just pick of the luck which one you get, I have Hynix chips on mine and they seem to reach 3200mhz just like the Samsung B-die chips without any problem, If you want to guarantee Samsung B-die chips, you need to get the CL14 3200mhz kit, much more expensive.
AMD RyZen had a lot of problems at first release running Hynix chips on memory and I think with the last bios update, this was one of their main concerns to get fixed.
However, G.skill also seem to use Samsung E-Die chips on those CL16 modules too, and those are the problem, not optimised in the bioses yet, but updates and fixes will come 2933mhz (3000mhz) is plenty fast enough, on first release you were lucky if you could get them to run above 2133mhz, just need to be patient for now.