MAINBOARD GIGABYTE B550M AORUS ELITE - 2Techshop
AMD B550 Ultra Durable Motherboard with Pure Digital VRM Solution, PCIe 4.0 x16 Slot, Dual PCIe 4.0/3.0 M.2 Connectors, Realtek GbE LAN, Smart Fan 5 with FAN STOP, RGB FUSION 2.0, Q-Flash Plus.
Dell Poweredge R750 Silver 4310 - TiGroup Website
Again, you have options with the R750, which can support 8x PCIe 4.0 x8 slots or up to 6x PCIe 4.0 x16 slots in 3x risers.
Asus TUF GAMING H670-PRO WIFI D4 Intel® ...
TUF GAMING B660M-E D4. Intel B660 (LGA 1700) mATX motherboard with PCIe 4.0 slot, two PCIe 4.0 M.2 slots, 10 Power stages, Realtek 2.5Gb Ethernet, DP, HDMI, front USB 3.2 Gen 2 Type-C, Aura Sync.