We start with a couple of benchmarks that mostly measure CPU performance. Even though AMD boards do not feature 'agressive turbo', which we sometimes see on the Intel platforms, there are options that increase performance while sacrificing power efficiency.
The differences in CPU performance are basically insignificant in all tests. There are no real differences between motherboards with B350 and X370 chipsets, at least in terms of performance. Only the cheapest models sometimes score a bit lower, however you won't notice this in practice at all.