ASUS PRIME B840M-A-CSM

ASUS Prime series motherboards are expertly engineered to unleash the full potential of AMD Ryzen™ 9000 series processors. The PRIME B840M-A-CSM motherboard provides users and PC DIY builders with a range of performance optimizations via intuitive software and firmware features. It’s designed to be Advanced AI PC-ready, offering the power and connectivity needed for demanding AI applications.

CPU

AMD Socket AM5 for AMD Ryzen™ 9000 & 8000 & 7000 Series Desktop Processors Refer to https://www.asus.com/support/download-center/ for CPU support list.

Chipset

AMD B840 Chipset

Memory

4 x DIMM slots, max. 192GB, DDR5Supports up to 7600+MT/s (OC) with Ryzen™ 9000 & 8000 & 7000 Series Processors, ECC and Non-ECC, Un-buffered DIMM*Dual channel memory architectureSupports AMD Extended Profiles for Overclocking (EXPO™)ASUS Enhanced Memory Profile (AEMP)* Supported memory types, data rate (speed), and number of DRAM modules vary depending on the CPU and memory configuration, for more information please refer to CPU/Memory Support list under the Support tab of product information site or visit https://www.asus.com/support/download-center/. Adjustments will be made based on the specifications of mass-produced memory products available on the market.* Non-ECC, un-buffered DDR5 memory supports On-Die ECC function.

Graphics

2 x DisplayPort1 x HDMI™ port Graphics specifications may vary between CPU types. Please refer to AMD CPU specifications. Supports max. 8K@30Hz as specified in DisplayPort 1.4. Supports 4K@60Hz as specified in HDMI 2.1.

Expansion Slots

AMD Ryzen™ 9000 & 7000 Series Desktop Processors*1 x PCIe 4.0 x16 slot (supports x16 mode)AMD Ryzen™ 8000 Series Desktop Processors1 x PCIe 4.0 x16 slot (supports x8/x4 mode)AMD B840 Chipset2 x PCIe 3.0 x16 slots (support x1 mode)* Please check the PCIe bifurcation table on the support site (https://www.asus.com/support/FAQ/1037507/). Specifications vary by CPU types.- To ensure compatibility of the device installed, please refer to https://www.asus.com/support/download-center/ for the list of supported peripherals.

Storage

Total supports 3 x M.2 slots and 4 x SATA 6Gb/s portsAMD Ryzen™ 9000 & 7000 Series Desktop ProcessorsM.2_1 slot (Key M), type 2280 (supports PCIe 4.0 x4 mode)M.2_2 slot (Key M), type 2242/2260/2280 (supports PCIe 4.0 x4 mode)AMD Ryzen™  8000 Series Desktop ProcessorsM.2_1 slot (Key M), type 2280 (supports PCIe 4.0 x4 mode)M.2_2 slot (Key M), type 2242/2260/2280 (supports PCIe 4.0 x4/x2 mode)*AMD B840 ChipsetM.2_3 slot (Key M), type 2280 (supports PCIe 3.0 x4 mode)4 x SATA 6Gb/s ports* Specifications vary by CPU types.AMD RAIDXpert2 TechnologyRyzen™ 9000 Series Processors: RAID 0/1/5/10Ryzen™ 8000 Series Processors: RAID 0/1Ryzen™ 7000 Series Processors: RAID 0/1/10

Ethernet

1 x Realtek 2.5Gb EthernetASUS LANGuard

USB

Rear USB (Total 7 ports)2 x USB 10Gbps ports (2 x Type-A)1 x USB 5Gbps port (1 x USB Type-C)4 x USB 2.0 ports (4 x Type-A)Front USB (Total 7 ports)1 x USB 5Gbps connector (supports USB Type-C)1 x USB 5Gbps header supports 2 additional USB 5Gbps ports2 x USB 2.0 headers support 4 additional USB 2.0 ports* USB Type-C power delivery output: max. 5V/3A

Audio

Realtek 7.1 Surround Sound High Definition Audio CODEC*- Supports: Jack-detection, Multi-streaming, Front Panel Jack-retasking- Supports up to 24-Bit/192 kHz playbackAudio Features- Audio Shielding- Premium audio capacitors- Dedicated audio PCB layers* A chassis with an HD audio module in the front panel is required to support 7.1 Surround Sound audio output.

Back Panel I/O Ports

2 x USB 10Gbps ports (2 x Type-A)1 x USB 5Gbps port (1 x USB Type-C)4 x USB 2.0 ports (4 x Type-A)2 x DisplayPort1 x HDMI™ port1 x Realtek 2.5Gb Ethernet port3 x Audio jacks1 x BIOS FlashBack™ button

Internal I/O Connectors

Fan and Cooling Related1 x 4-pin CPU Fan header1 x 4-pin CPU OPT Fan header2 x 4-pin Chassis Fan headersPower Related1 x 24-pin Main Power connector1 x 8-pin +12V CPU Power connectorStorage Related3 x M.2 slots (Key M)4 x SATA 6Gb/s portsUSB1 x USB 5Gbps connector (supports USB Type-C )1 x USB 5Gbps header supports 2 additional USB 5Gbps ports2 x USB 2.0 headers support 4 additional USB 2.0 portsMiscellaneous3 x Addressable Gen 2 headers1 x Clear CMOS header1 x COM Port header1 x Front Panel Audio header (F_AUDIO)1 x S/PDIF Out header1 x SPI TPM header (14-1 pin)1 x 10-1 pin Front Panel System header

Special Features

ASUS 5X PROTECTION III- DIGI+ VRM- LANGuard- Overvoltage protection- SafeSlot Core+- Stainless-steel back I/OASUS Q-Design- Q-Dashboard- Q-DIMM- Q-LED Core- Q-SlotASUS Thermal Solution- M.2 heatsink- VRM heatsink designASUS EZ DIY- BIOS FlashBack™ button- BIOS FlashBack™ LED- Pre-mounted I/O shieldAura Sync- Addressable Gen 2 headers

Software Features

ASUS Exclusive SoftwareArmoury Crate- Aura Creator- Aura Sync- Fan Xpert 2+- Power SavingASUS DriverHubTurboV CoreASUS CPU-ZAdobe Creative Cloud (Free Trial)Norton 360 Deluxe (60 Days Free Trial)WinRAR (40 Days Free Trial)UEFI BIOSASUS EZ DIY- ASUS CrashFree BIOS 3- ASUS EZ Flash 3- ASUS UEFI BIOS EZ Mode- ASUS MyHotkey

Remote Management Features

IT Management software supported- ASUS Control Center Express (ACCE)

BIOS

256 Mb Flash ROM, UEFI AMI BIOS

Manageability

WOL by PME, PXE

Accessories

Cables2 x SATA 6Gb/s cablesMiscellaneous1 x M.2 rubber package2 x Screw packages for M.2 SSDDocumentation1 x ACC Express Activation Key Card1 x Quick start guide

Operating System

Windows 11, Windows 10 64-bit

Form Factor

micro-ATX Form Factor9.6 inch x 9.6 inch (24.4 cm x 24.4 cm)