AMD Ryzen 5000 Vermeer processors are now functional on X370 chipset motherboards
ASRock X370 motherboards are gaining access to Ryzen 5000 processors via a BIOS update. The update remains in Alpha currently, but the BIOS has already been published on the JZelectronic forums. It should go without saying that the BIOS should only be used for testing purposes, and has not been tested thoroughly enough for use by anyone other enthusiasts who know what they are doing.
So far, the P6.61 BIOS has been shown working on an X370 Taichi motherboard with a Ryzen 5 5600X processor. When we say working, we mean that Vermeer processors can boot to BIOS on ASRock X370 motherboards; there is no evidence of how stably the P6.61 BIOS behaves when Windows is loaded.
JZelectronic has not explained what Ryzen 5000 features the P6.61 BIOS brings to X370 motherboards, nor will AMD or ASRock comment on the matter. According to Tom's Hardware, AMD stated the following when asked about bringing Ryzen 5000 support to 300-series motherboards:
AMD has no plans to enable or support AMD Ryzen 5000 series on AMD 300 series chipsets.
Overall, we would not recommend unofficially Alpha testing a BIOS. There is a chance that the P6.61 BIOS has been modified from a working X470 BIOS with Ryzen 5000 support, but confirming that may be tricky unless someone claims ownership to it.