https://wccftech.com/asus-rolls-out-amd-agesa-1-2-0-6-beta-bios-firmware-rog-crosshair-viii-motherboards/

ASUS is the first motherboard manufacturer to start rolling out the latest AMD AGESA 1.2.0.6 BETA BIOS firmware on its ROG Crosshair VIII series motherboards.

So far, AMD's motherboard partners have gradually been rolling out BETA AGESA Firmware BIOS updates on their respective 500 & 400-series motherboards. There are also new BIOS rolling out that are specifically designed to support AMD Ryzen 5000 Desktop CPUs on the older 300-series motherboards though board vendors haven't opened them up to the entire lineup as they are still waiting on AMD's final call. More information here in regards to the whole Ryzen 5000 CPU support on 300-series motherboards.