Quick overview from the supplier:
MB AM4 ASRock B550M PHANTOM GAMING 4 mATX
// CPU
- AMD AM4 Socket
- Supports 3rd Gen AMD AM4 Ryzen™ / future AMD Ryzen™ Processors*
Chipset
- AMD B550
Memory
- Dual Channel DDR4 Memory Technology
- 4 x DDR4 DIMM Slots
- DDR4 4733+(OC) / 4666(OC) / 4600(OC) / 4533(OC) / 4466(OC) / 4400(OC) / 4333(OC) / 4266(OC) / 4200(OC) / 4133(OC) / 4000(OC) / 3866(OC) / 3800(OC) / 3733(OC) / 3600(OC) / 3466(OC) / 3200 / 2933 / 2667 / 2400 / 2133 ECC & non-ECC, un-buffered memory*
- Max. capacity of system memory: 128GB**
Graphics
- Shared memory default 2GB. Max Shared memory supports up to 16GB.**
- Dual graphics output: support HDMI and DisplayPort 1.4 ports by independent display controllers
- Supports HDMI 2.1 with max. resolution up to 4K x 2K (4096x2160) @ 60Hz
- Supports DisplayPort 1.4 with max. resolution up to 5K (5120x2880)@120Hz
Audio
- 7.1 CH HD Audio (Realtek ALC887/897 Audio Codec)
LAN
- PCIE x1 Gigabit LAN 10/100/1000 Mb/s
- Realtek RTL8111H
Slots
- 2 x PCI Express x16 Slots (PCIE1: Gen4x16 mode; PCIE3: Gen3 x4 mode)*
- 1 x PCI Express 3.0 x1 Slot
- Supports AMD Quad CrossFireX™ and CrossFireX™
Storage
- 4 x SATA3 6.0 Gb/s Connectors, support RAID (RAID 0, RAID 1 and RAID 10), NCQ, AHCI and Hot Plug
- 1 x Hyper M.2 Socket (M2_1), supports M Key type 2280 M.2 PCI Express module up to Gen4x4 (64 Gb/s) (with Matisse) or Gen3x4 (32 Gb/s) (with Renoir)*
- 1 x M.2 Socket (M2_2), supports M Key type 2280 M.2 SATA3 6.0 Gb/s module and M.2 PCI Express module up to Gen3 x2 (16 Gb/s)*
USB
- 8 x USB 3.2 Gen1 Ports
- 6 x USB 2.0 Ports
https://www.asrock.com/MB/AMD/B550M%20Phantom%20Gaming%204/index.asp#Overview
