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MSI MAG B550M MORTAR - mATX, AM4, 4xDDR4, 2xM.2, 1xDP, 1xHDMI, 2-Way CrossFire
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Type Detail:
AMD Socket AM4
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Quick Tech Specs

Processor Manufacture: AMD
Socket: AM4
Brand: MSI
Chipset Manufacture: AMD / B550
Form Factor: Micro ATX
SLI Support: NONE
Crossfire Support: YES
Number of Memory Slots: 4 Slots
Max Memory: 128GB
Memory Type: DDR4
PCI Express x16 Slots: 2 Slots
PCI Express x1 Slots: 2 Slots
PCI Slots: None
WiFi Onboard: NONE
RAID Support: RAID 0/1/10
Sata 6 Gbits/s Ports (3.0/3.1): 6 Ports
Sata 3 Gbits/s Ports (2.0): None
Sata Express 16 Gbits/s Ports (3.2): None
M.2 Slots: 2 Slots
NVMe Support: No
eSata Ports: None
USB C Ports: 1 Port
Network Ports: 2.5 Gigabit
USB 3.x Ports (3.0 or higher): 3 ports
Legacy Ports: NONE
Thunderbolt Ports: NONE
USB 3.0 Ports: None
USB 2.0 Ports: 2 Ports
Display Ports: 1 Port
HDMI Ports: 1 Ports


The MAG series was born through rigorous quality testing and designed to be a symbol of sturdiness and durability. Focused on providing the best user experience, the MAG series has a simple installation process coupled with a friendly user interface making it the best choice for entry level gamers.

Form Factor

  • Micro-ATX Form Factor, 9.6 in. x 9.6 in. (24.4 cm x 24.4 cm)


  • Supports AM4 socket 3rd Gen AMD Ryzen™ processors, and future AMD Ryzen™ processors with BIOS update


  • AMD B550 Chipset


  • 4x DDR4 memory slots, support up to 128 GB, Supports DDR4 1866/ 2133/ 2400/ 2667/ 2800/ 2933/ 3000/ 3066/ 3200 MHz by JEDEC, Supports DDR4 2667/ 2800/ 2933/ 3000/ 3066/ 3200/ 3466/ 3600/ 3733/ 3866/ 4000/ 4133/ 4266/ 4400+ MHz by A-XMP OC MODE, 1DPC 1R max speed 4400 MHZ, 1DPC 2R max speed 3733 MHZ, 2DPC 1R max speed 3866 MHZ, 2DPC 2R max speed 3466 MHZ, Dual channel memory architecture, Supports non-ECC UDIMM memory, Supports ECC UDIMM memory (non-ECC mode), Supports un-buffered memory


  • 1x HDMI port, supports a maximum resolution of 4096x2160 @24Hz, 1x DisplayPort, supports a maximum resolution of 4096x2160 @60Hz, Maximum shared memory of 2048 MB


  • Supports 2-Way AMD CrossFire™ Technology

Expansion Slots

  • 1x PCIe 3.0/ 4.0 x16 slot (PCI_E1), 1x PCIe 3.0 x16 slot (PCI_E4), supports x4 mode, 2x PCIe 3.0 x1 slots


  • AMD B550 Chipset; 6x SATA 6Gb/s ports, 2x M.2 slots (Key M), M2_1 slot (from AMD processor), Supports PCIe 4.0/ 3.0 x4 1, Supports SATA 6Gb/s, Supports 2242/ 2260/ 2280 storage devices, M2_2 slot (from AMD B550 chipset), Supports PCIe 3.0x4, Supports 2242/ 2260/ 2280 storage devices, The supported specification depends on installed processor. RAID; AMD B550 Chipset; Supports RAID 0, RAID 1 and RAID 10 for SATA storage devices Supports RAID 0 and RAID 1 for M.2 NVMe storage devices


  • 1x Realtek® RTL8125B 2.5Gbps LAN controller


  • Realtek® ALC1200 Codec, 7.1-Channel High Definition Audio, Supports S/PDIF output

USB Ports

  • AMD B550 Chipset; 3x USB 3.2 Gen 1 5Gbps ports (1 Type-C internal connector, and 2 ports are available through the internal USB 3.2 Gen 1 5Gbps connector), 6x USB 2.0 ports (2 Type-A ports on the back panel, 4 ports through the internal USB 2.0 connectors), AMD Processor; 2x USB 3.2 Gen 2 10Gbps ports (1 Type-C port and 1 Type-A port on the back panel), 2x USB 3.2 Gen 1 5Gbps Type-A ports on the back panel

OS Support

  • Windows® 10 64-bit

Internal I/O Ports

  • 1x 24-pin ATX main power connector, 1x 8-pin ATX 12V power connector, 6x SATA 6Gb/s connectors, 2x M.2 slots (M-Key), 1x USB 3.2 Gen 1 5Gbps Type-C port, 1x USB 3.2 Gen 1 5Gbps connector (supports additional 2 USB 3.2 Gen 1 5Gbps ports), 2x USB 2.0 connectors (supports additional 4 USB 2.0 ports), 1x 4-pin CPU fan connector, 1x 4-pin water-pump fan connector, 3x 4-pin system fan connectors, 1x Front panel audio connector, 2x System panel connectors, 1x Chassis Intrusion connector, 1x 4-pin RGB LED connector, 2x 3-pin RAINBOW LED connectors, 1xTPM module connector, 1x Clear CMOS jumper

Back I/O Ports

  • DisplayPort, PS/2 Combo Port, 2.5G LAN Port, 1 x USB 3.2 Gen 2 10Gbps (Type-A), HD Audio Connectors, HDMI Port, Flash BIOS Button, 2 x USB 2.0 port, 2 x USB 3.2 Gen 1 5Gbps (Type-A), 1 x USB 3.2 Gen 2 10Gbps (Type-C), Optical S/PDIF OUT