B450 AORUS Elite V2 (rev. 1.x) Key Features | Motherboard - GIGABYTE Global
X470, B450, X370 Motherboards with BIOS Flashback/Ryzen 3000 Ready
Amazon.com: MSI Performance Gaming AMD Ryzen 1st, 2nd, and 3rd Gen AM4 M.2 USB 3.2 Gen 2 DDR4 HDMI Display Port Wi-Fi ATX Motherboard (B450 Gaming PRO Carbon MAX WiFi) : Everything
Top 5 Best B450 Motherboards (for Ryzen 3000 / 5000)
Does the B450 support the new Ryzen 3rd Gen CPUs out of the box? - Quora
Asrock B450m Steel Legend came with a Ryzen 3000 ready bios out of the box from Amazon. : r/Amd