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MSI MEG B550 UNIFY-X AM4 AMD B550 USB 3.0 ATX AMD Motherboard

  • AMD B550
  • Supports AMD Ryzen 5000 & 3000 Series desktop processors (not compatible with AMD Ryzen 5 3400G & Ryzen 3 3200G) and AMD Ryzen 4000 G-Series desktop processors
  • AMD Ryzen 4000 G-Series processors support DDR4 5300+ (Max. 5800)/ 5100/ 5000/ 4866/ 4800/ 4733/ 4600/ 4533/ 4400/ 4266/ 4133/ 4000/ 3866/ 3733/ 3600/ 3466/ 3200/ 3066/ 3000/ 2933/ 2800/ 2667 MHz by A-XMP OC MODE
  • 3rd Gen AMD Ryzen processors supports DDR4 5100+/ 5000/ 4866/ 4800/ 4733/ 4600/ 4533/ 4400/ 4266/ 4133/ 4000/ 3866/ 3733/ 3600/ 3466/ 3200/ 3066/ 3000/ 2933/ 2800/ 2667 MHz by A-XMP OC MODE
  • Supports DDR4 3200/ 3066/ 3000/ 2933/ 2800/ 2667/ 2400/ 2133/ 1866 MHz by JEDEC
  • AMD Ryzen 4000 G-Series processors:
  • 1DPC 1R max speed 5300 MHz (QVL), Max. 5800 MHz
  • 1DPC 2R max speed 4266 MHz (QVL), Max. 4600 MHz
  • 3rd Gen AMD Ryzen processors:
  • 1DPC 1R max speed 5100 MHz (QVL), Max. 5300 MHz
  • 1DPC 2R max speed 4260 MHz (QVL)
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Specs
Reviews (12)

Learn more about the MSI MEG B550 UNIFY-X

Model
Brand MSI
Model MEG B550 UNIFY-X
Supported CPU
CPU Socket Type AM4
CPU Type Supports AMD Ryzen 5000 & 3000 Series desktop processors (not compatible with AMD Ryzen 5 3400G & Ryzen 3 3200G) and AMD Ryzen 4000 G-Series desktop processors
Chipsets
Chipset AMD B550
Memory
Number of Memory Slots 2x288pin (DDR4)
Memory Standard AMD Ryzen 4000 G-Series processors support DDR4 5300+ (Max. 5800)/ 5100/ 5000/ 4866/ 4800/ 4733/ 4600/ 4533/ 4400/ 4266/ 4133/ 4000/ 3866/ 3733/ 3600/ 3466/ 3200/ 3066/ 3000/ 2933/ 2800/ 2667 MHz by A-XMP OC MODE
3rd Gen AMD Ryzen processors supports DDR4 5100+/ 5000/ 4866/ 4800/ 4733/ 4600/ 4533/ 4400/ 4266/ 4133/ 4000/ 3866/ 3733/ 3600/ 3466/ 3200/ 3066/ 3000/ 2933/ 2800/ 2667 MHz by A-XMP OC MODE
Supports DDR4 3200/ 3066/ 3000/ 2933/ 2800/ 2667/ 2400/ 2133/ 1866 MHz by JEDEC

AMD Ryzen 4000 G-Series processors:
1DPC 1R max speed 5300 MHz (QVL), Max. 5800 MHz
1DPC 2R max speed 4266 MHz (QVL), Max. 4600 MHz
3rd Gen AMD Ryzen processors:
1DPC 1R max speed 5100 MHz (QVL), Max. 5300 MHz
1DPC 2R max speed 4260 MHz (QVL)
Maximum Memory Supported 64GB
Channel Supported Dual Channel
Expansion Slots
PCI Express 4.0 x16 1 x PCIe 4.0/3.0 x16 slot (PCI_E1) *
* The supported specification depends on installed processor.
PCI Express 3.0 x16 1 x PCIe 3.0 x16 slot (PCI_E4), supports x4 speed
* The PCI_E4 slot will be unavailable, when installing M.2 SSD into M2_4.
PCI Express x16 1 x PCI Express x16
PCI Express x1 2 x PCIe 3.0 x1 slots (PCI_E2 & PCI_E3)
* The both PCIe x1 slots will be unavailable after you install the M.2 SSD into M2_2 slot in Chipset support mode (default mode).
Storage Devices
Serial ATA (SATA) 6 x SATA 6Gb/s ports 1 2
1. The SATA5 port will be unavailable when installing M.2 SATA SSD into M2_3.
2. The SATA5 and SATA6 ports will be unavailable when installing M.2 PCIe SSD into M2_3.
M.2 4 x M.2 slots (Key M)
M2_1 slot (from CPU):
Supports PCIe 4.0/3.0 x4*
Supports SATA 6Gb/s
Supports 2280/22110 storage devices
M2_2 slot:
Chipset support mode (default, from Chipset ) - supports PCIe 3.0 x2
CPU support mode (From CPU) - supports PCIe 4.0/3.0 x4 *
Supports 2280 storage devices
M2_3 slot:
Chipset support mode (default, from Chipset ) - supports PCIe 3.0 x2
CPU support mode (From CPU) - supports PCIe 4.0/3.0 x4 *
Supports SATA 6Gb/s
Supports 2280/22110 storage devices
M2_4 slot:
Supports PCIe 3.0 x4
Supports 2280 storage devices

* M.2 specifications may vary depending on the CPU installed.
SATA RAID 0/1/10
Onboard Video
Onboard Video Chipset Supported only by CPU with integrated graphic:
1 x HDMI 2.1 port, supporting a maximum resolution of 4096x2160 @120 Hz 1 2
Maximum shared memory of 16GB

1. Available for the processor with integrated graphics.
2. Graphics specifications may vary depending on the CPU installed.
Onboard Audio
Audio Chipset Realtek ALC1220P Codec
Audio Channels 7.1-Channel High Definition Audio
Supports S/PDIF output
Onboard LAN
LAN Chipset Realtek RTL8125B
Max LAN Speed 2.5Gbps
Wireless LAN Intel Wi-Fi 6 AX200
The Wireless module is pre-installed in the M.2 (Key-E) slot
Supports MU-MIMO TX/RX, 2.4GHz/5GHz (160MHz) up to 2.4Gbps
Supports 802.11 a/ b/ g/ n/ ac/ ax
Bluetooth Supports Bluetooth 5.1
Rear Panel Ports
Back I/O Ports 4 x USB 3.1 Gen 1
USB 3.0 4 x USB 3.0
Internal I/O Connectors
Onboard USB 1 x USB 3.2 Gen 2 10Gbps Type-C port
1 x USB 3.2 Gen 1 5Gbps connector (supports additional 2 USB 3.2 Gen 1 5Gbps ports)
2 x USB 2.0 connectors (supports additional 4 USB 2.0 ports)
Other Connectors 1 x 4-pin CPU fan connector
1 x 4-pin water-pump fan connector
6 x 4-pin system fan connectors
1 x Front panel audio connector
2 x System panel connectors
1 x Chassis Intrusion connector
1 x 4-pin RGB LED connectors
2 x 3-pin RAINBOW LED connectors
1 x 3-pin CORSAIR LED connector
1 x TPM module connector
1 x Clear CMOS jumper
1 x Power button
1 x Reset button
Physical Spec
Form Factor ATX
LED Lighting RGB
Dimensions (W x L) 12.0" x 9.6"
Power Pin 1 x 24-pin ATX main power connector
2 x 8-pin ATX 12V power connector
1 x 6-pin PCIE power connector
Software Feature
Windows 11 Supported
Features
Features Supports AMD Ryzen 5000 & 3000 Series desktop processors (not compatible with AMD Ryzen 5 3400G & Ryzen 3 3200G) and AMD Ryzen 4000 G-Series desktop processors.
Supports DDR4 Memory, Dual Channel 5300(OC) MHz+ (MAX5800).
Quadruple M.2 Connectors: Maximum onboard 4 x M.2 slots, support the latest Gen 4 solution with up to 64GB/s bandwidth for maximum transfer speed.
Extreme Power Design: Direct 14+2 phases with 90A Power Stage and dual CPU power connectors to unleash your true power.
Premium Thermal Solution: Aluminum Cover with additional choke thermal pad rated for 7W/mk and PCB with 2oz thickened copper are built for high performance system and non-stop gaming experience.
2.5G LAN with LAN Manager and Intel Wi-Fi 6 AX Solution: Upgraded network solution for professional and multimedia use. Delivers a secure, stable and fast network connection.
Lightning Fast Game experience: PCIe 4.0, Lightning Gen 4 x4 M.2 with M.2 double-side Shield Frozr, AMD Turbo USB 3.2 GEN 2.
Flash BIOS Button with Optmized ClearCMOS Function: Simply use a USB key to flash any BIOS within seconds. Restore the BIOS to the default settings without any additional actions.
Pre-installed I/O Shield: Better EMI protection and more convenience for installation.
Additional Information
First Listed on Newegg October 09, 2025

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