MSI PRO B840M-B

PRO B840M-B is engineered with many exclusive features of MSI, PCIe 4.0 M.2, EZ PCIe Clip II, 2.5G LAN, and Front Type-C, ready for the AMD Ryzen 9000 series processors.

CPU

Supports AMD Ryzen™ 9000/ 8000/ 7000 Series Desktop Processors
Socket AM5

Chipset

AMD B840

Memory

2x DDR5 UDIMM, Maximum Memory Capacity 128GB
Memory Support DDR5 8000 - 5600 (OC) MT/s / 5600 - 4800 (JEDEC) MT/s
Ryzen™ 9000 Series Processors max. overclocking frequency:
• 1DPC 1R Max speed up to 8000+ MT/s
• 1DPC 2R Max speed up to 7200+ MT/s

Supports AMD POR Speed and JEDEC Speed
Supports Memory Overclocking and AMD EXPOTM
Supports Dual-Channel mode
Supports Non-ECC, Un-buffered memory
Supports CUDIMM, Clock Driver bypass mode only*

* CUDIMM support and POR boot frequency may vary by CPU series, with manual overclocking available after boot. Certain CPUs may fail to boot, but future BIOS updates will improve compatibility.
• The DIMM slots on this motherboard have single-sided latches.
• Memory compatibility and supported speeds can vary depending on the CPU and memory configuration. For detailed information, please refer to the Memory Compatibility List available on the product’s Support page or visit https://www.msi.com/support/.

Onboard Graphics

1x HDMI™
Support HDMITM 2.1, maximum resolution of 4K 60Hz*
1x VGA
Support VGA, maximum resolution of 2048x1536 50Hz, 2048x1280 60Hz, 1920x1200 60Hz*
*Available only on processors featuring integrated graphics. Graphics specifications may vary depending on the CPU installed.

Expansion Slots

1x PCI-E x16 slot
1x PCI-E x1 slot
PCI_E1 Gen PCIe 4.0 supports up to x16 (From CPU)
PCI_E2 Gen PCIe 3.0 supports up to x1 (From Chipset)

PCI_E1 slot
• Supports PCIe 4.0 x16 (For Ryzen™ 9000/ 7000 Series processors)
• Supports PCIe 4.0 x8 (For Ryzen™ 8700/ 8600/ 8400 Series processors)
• Supports PCIe 4.0 x4 (For Ryzen™ 8500/ 8300 Series processors)

Audio

Realtek ALC897
7.1-Channel High Definition Audio

Storage

2x M.2
M.2_1 Source (From CPU) supports up to PCIe 4.0 x4 , supports 2280/2260 devices
M.2_2 Source (From CPU) supports up to PCIe 4.0 x4 , supports 2280/2260 devices
4x SATA 6G

M2_2 slot
• Supports up to PCIe 4.0 x4
• Supports up to PCIe 4.0 x2 (For Ryzen™ 8500/ 8300 Series processors)

Supports RAID 0, RAID 1 and RAID 10 for SATA storage devices
Supports RAID 0 and RAID 1 for M.2 NVMe storage devices

USB

2x USB 2.0 (Rear)
4x USB 2.0 (Front)
4x USB 5Gbps Type A (Rear)
2x USB 5Gbps Type A (Front)
1x USB 5Gbps Type C (Front)

LAN

Realtek 8125D 2.5G LAN

Internal I/O

1x Power Connector(ATX_PWR)
1x Power Connector(CPU_PWR)
1x CPU Fan
2x System Fan
2x Front Panel (JFP)
1x Chassis Intrusion (JCI)
1x Front Audio (JAUD)
1x Com Port (JCOM)
3x Addressable V2 RGB LED connector (JARGB_V2)
1x RGB LED connector(JRGB)
1x TPM pin header(Support TPM 2.0)
4x USB 2.0 ports
2x USB 5Gbps Type A ports
1x USB 5Gbps Type C ports

Back Panel I/O

1x Clear CMOS Button
1x HDMI™
1x VGA
4x USB 5Gbps Typ-A
1x 2.5G LAN
3x Audio connectors
1x Flash BIOS Button
2x USB 2.0

Operating System

Support for Windows 11 64-bit

Form Factor

mATX
226 x 244 mm