GIGABYTE AM4 Motherboards: PCIe 4.0 Ready for Ryzen 3000
MSI B550 GAMING PLUS (Socket AM4) USB-C Gen 2 AMD ATX GAMING Motherboard PCIE Gen 4 Black B550GPLUS - Best Buy
NeweggBusiness - ASRock B550M Pro SE AM4 DDR4 SATA 6Gb/s 1 PCIe 4.0 x16 Micro ATX Motherboard
ASUS PRIME B760M-A AX D4 Intel B760 (LGA 1700)((13th and 12th Gen) mATX
MSI PRO B550-VC ProSeries Motherboard AMD AM4 DDR4 - NWCA Inc.
ASUS Prime B550M-A/CSM AMD AM4 (3rd Gen Ryzen) microATX Commercial Motherboard (PCIe 4.0, ECC Memory, 1Gb LAN, HDMI 2.1/D-Sub, 4K@60HZ, TPM, ASUS Control Center Express) - Walmart.com
Amazon.com: MSI MAG X570S Tomahawk WiFi Motherboard (AMD AM4, DDR4, PCIe 4.0, SATA 6Gb/s, M.2, USB 3.2 Gen 2, AC Wi-Fi 6, HDMI, ATX) : Everything Else
B550 motherboard guide: ASUS and AMD bring PCI Express 4.0 to everyone with ROG Strix, TUF Gaming, and Prime - Edge Up
Amazon.com: MSI MPG B550 GAMING PLUS Gaming Motherboard (AMD AM4, DDR4, PCIe 4.0, SATA 6Gb/s, M.2, USB 3.2 Gen 2, HDMI/DP, ATX) : Electronics
AM4 Motherboard MSI B550M PRO-VDH WIFI, PCIe 4.0/ 3.0 x16 slot 4 SATA 6Gb/s ports M.2 Support Wi-Fi 802.11 For Ryzen 5 5600 - AliExpress
ASUS PRIME B550M-A/CSM AM4 Micro ATX AMD Motherboard - Newegg.com