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Product specifications

ASUS PRIME B840M-A WIFI-CSM motherboard AMD B840 Socket AM5 micro ATX

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Prime B840M-A WIFI-CSM

Part PRIME B840M-A WIFI-CSM · UPC 197105797154

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About this product

ASUS Prime series motherboards are expertly engineered to unleash the full potential of AMD Ryzen™ 9000 series processors. The PRIME B840M-A WIFI-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.

ASUS Corporate Stable Model

ASUS Corporate Stable Model (CSM) is a commercial program designed to provide stable and reliable motherboards. Offering up to 36-month product lifecycle support and 6-month end-of-life notice to allow sufficient lead times for your organization to get ready for product transitions. Each purchase of an ASUS CSM motherboard comes with ASUS Control Center Express - server-grade IT management software.

ASUS Control Center Express

ASUS Control Center Express is an integrated IT monitoring and management software designed to deploy faster, simplify IT operations and improve productivity with comprehensive control and user-friendly functions. ASUS Control Center Express is compatible with over 100 ASUS motherboards to provide a high-quality, TCO-optimized solution for your business needs.

Optimize IT endpoint management

Designed to assist IT staff in monitoring and controlling devices within their corporate networks, and facilitate inventory checking in multiple locations remotely.

Automate IT maintenance

Allows IT staff to schedule automatic updates of the latest BIOS, software and utilities to specific or all devices at off-peak times, enhancing system stability and IT operational flexibility.

Securely manage all of endpoints

Securely manage endpoint configuration, portable storage access and PC software applications by enabling them to create grouping rules on individual devices.

Performance

AI Solutions

ASUS AI Solutions include AI Advisor as your technical expert with expertise in PC performance.

AI Advisor

ASUS AI Advisor allows users to explore the functionality and advanced features of ASUS motherboards in a simple and straightforward way.8

Performance

Digital Power Design

PRIME B840M-A WIFI-CSM features an 8+2+1 phase power design with discrete MOSFETs, ensuring efficient and stable power delivery for AMD processors plus steady performance for day-to-day use.6

The multi-layered printed circuit board design quickly dissipates heat around the voltage regulators to improve overall system stability and provide the CPU with more overclocking headroom.

The Power Saving function contains several settings to easily optimize power consumption and maximize energy savings. You can enable a CPU power limit, darken Aura lighting and set the fan profile to a Power Saving mode. You can also toggle the Power Saver plan that is built into Microsoft Windows.

The Digi+ voltage-regulator module (VRM) delivers real-time control over voltage droop, automatically switching frequency and power-efficiency settings.

Enhanced Memory & Storage Performance

Enhanced DDR5 performance

Comprehensive memory tuning options are the cornerstone of PRIME motherboards. The PRIME B840M-A WIFI-CSM maximizes the potential of your DDR5 modules, from entry-level to extreme-speed kits.2

For entry-level modules without EXPO™ support, ASUS Enhanced Memory Profile (AEMP) automatically detects memory chips and provides optimized profiles for enhanced performance.

For those looking to surpass stock DDR5 speeds, the PRIME B840M-A WIFI-CSM offers extensive AMD Extended Profiles for Overclocking (EXPO™) support and a wide array of UEFI settings for further performance tweaks.3

Three M.2 slots (up to 64 Gbps)

PRIME B840M-A WIFI-CSM offers a total of three M.2 slots, including two that support data-transfer speeds of up to 64 Gbps via PCIe 4.0, and one that supports PCIe 3.0. This enables quicker boot-up and app load times with OS or application drives.4

Cooling

Cooler by design

The PRIME B840M-A WIFI-CSM motherboard is engineered with multiple onboard heatsinks and an array of hybrid fan headers to help ensure your rig stays cool and stable under intense workloads.

Smart Cooling precision

ASUS Fan Xpert 2+

ASUS Fan Xpert 2+ software provides comprehensive control over fans. An Auto-Tuning mode intelligently configures all parameters with a single click. There’s also an Extreme Quiet mode that reduces chassis fan speeds to below the default minimum to keep your system whisper-quiet when performing light tasks. Fans can also be controlled via the UEFI BIOS.6

Cooler compatibility

ASUS AIO coolers offer robust performance, high overclocking potential, bold aesthetics and customizable functionality for new motherboards, empowering you to build your dream gaming rig.6

Flexibility

Empowering connections

This motherboard offers a versatile range of connectivity, including support for WiFi 6E, PCIe 4.0 slot and an arsenal of USB ports which includes Type-C® connections.

WiFi 6E

Built-in WiFi 6E5 technology takes advantage of the newly available radio spectrum in the 6 GHz band. With triple the bandwidth of the 2.4/5/6 GHz band, WiFi 6E delivers ultrafast wireless networking speeds with improved capacity and better performance in dense wireless environments.

Realtek 2.5 Gb Ethernet

Realtek 2.5 Gb Ethernet reduces CPU overhead and offers exceptionally high TCP and UDP throughput for faster, smoother data transfers.

Front USB 5Gbps Type-C®

This motherboard features a USB 5Gbps Type-C® front panel connector for speedy data transfers of up to 5Gbps.6

Customization

Personalization

The PRIME B840M-A WIFI-CSM enhances the user experience across the board, from simplifying BIOS setting adjustments to offering customizable RGB lighting controls for a uniquely personal system aesthetic.

UEFI BIOS

The UEFI interface delivers easy-to-use configuration options for PC beginners, and advanced features for veterans.

ASUS GlideX

Enable seamless screen sharing and control across PCs, tablets, and smartphones via wired or wireless connections, supporting multiple platforms.

ASUS DriverHub

Simplify driver management with automatic detection, one-click installation and update for smooth, efficient system performance.

Armoury Crate

Customize Aura Sync RGB and control ASUS devices. Includes product registration and updates.

Aura Sync

Complete RGB lighting control for enthusiast systems, ensuring seamless synchronization with compatible hardware.

Addressable Gen 2 RGB headers

Three addressable Gen 2 headers detect LED counts on compatible RGB devices, automatically adjusting lighting effects accordingly.

Customization

DIY friendly

The PRIME B840M-A WIFI-CSM motherboard features EZ PC DIY innovations that simplify and speed up the PC building process, making DIY easy and convenient.

Q-Antenna

With Q-Antenna, attaching a WiFi antenna to your PC is now easy and fast. Instead of slowly rotating two fasteners until they finally lock in, they just snap into place. Less hassle, and more consistent performance.7

Q-LED Core

The Q-LED Core display produces color-coded lights during the Power-On Self-Test (POST) that can help you troubleshoot potential issues.

Pre-Mounted I/O Shield

Our pre-installed I/O shield safeguards ports, simplifies the build process, increases functionality and enhances aesthetics for PC DIY enthusiasts.

BIOS FlashBack™

BIOS FlashBack™ simplifies BIOS updates. Just load the BIOS file onto a FAT32 USB stick, insert it into the BIOS FlashBack™ port, and press a button—no CPU or memory needed.

SafeSlot Core+

SafeSlot Core+ is a one-piece stainless-steel brace that shields the slot to protect it from damage. The metal cover is tightly secured to the slot with hooks, and the entire assembly is firmly anchored to the PCB with strengthened solder points to provide a secure foundation for heavyweight graphics cards.

Build for the most advanced pc for gaming and creating

When only the fastest will do, ASUS motherboards deliver. With faster dual-channel DDR5 memory support, AMD EXPO™ technology and PCIe® 4.0 support for both graphics and NVMe, you can play the most demanding games and deliver your biggest projects with the revolutionary performance of an ASUS motherboard and AMD Ryzen™ 9000, 8000, and 7000 Series processors.

Manufacturer notes

© 2024 Advanced Micro Devices, Inc. All rights reserved. AMD, the AMD Arrow logo, Radeon, Ryzen and combinations thereof are trademarks of Advanced Micro Devices, Inc. Other product names used in this publication are for identification purposes only and may be trademarks of their respective owners. On the back of the motherboard. Memory overclocking may vary between CPU series. Please refer to the spec table for detailed information. Supported memory types, data rates (speed), and number of DRAM modules vary depending on the CPU and memory configuration. For more information, please refer to the CPU/Memory Support List under the Support tab on the product information page or visit https://www.asus.com/support/download-center/. Actual transmission speeds will be lower than the theoretical maximum speed. WiFi 6E availability and features are dependent on regulatory limitations and co-existence with 5 GHz WiFi. Image(s) for reference only. Video(s) for reference only. Availability of ASUS AI Advisor may vary by region. AI Advisor functions may vary by platform.

Processor

Processor manufacturer
AMD
Processor socket
Socket AM5
Compatible processor series
AMD Ryzen 7000 Series, AMD Ryzen 8000 Series, AMD Ryzen 9000 Series
Supported processor sockets
Socket AM5

Memory

Supported memory types
DDR5-SDRAM
Number of memory slots
4
Memory slots type
DIMM
Memory channels
Dual-channel
ECC сompatibility
ECC & Non-ECC
Supported memory clock speed (max)
7600 MHz
Maximum internal memory
192 GB
Unbuffered memory
Yes

Storage controllers

Supported storage drive types
HDD & SSD
Supported storage drive interfaces
M.2, SATA III
Number of HDDs supported
4
Number of storage drives supported
7
RAID support
Yes
RAID levels
0, 1, 5, 10

Graphics

Parallel processing technology support
Not supported
On-board graphics card
No
Maximum resolution
7680 x 4320 pixels

Internal I/O

USB 2.0 connectors
2
USB 3.2 Gen 1 (3.1 Gen 1) connectors
2
Number of SATA III connectors
4
S/PDIF out connector
Yes
Front panel audio connector
Yes
Front panel connector
Yes
ATX Power connector (24-pin)
Yes
CPU fan connector
Yes
Number of CPU fan connectors
2
Number of chassis fan connectors
3
EPS power connector (8-pin)
Yes
Number of EPS power connectors (8-pin)
1
Number of COM connectors
1
TPM connector
Yes
Number of water pump connectors
1
RGB LED pin header
Yes
Number of RGB LED pin headers
3

Rear panel I/O ports

USB 2.0 ports quantity
4
USB 3.2 Gen 1 (3.1 Gen 1) Type-C ports quantity
1
USB 3.2 Gen 2 (3.1 Gen 2) Type-A ports quantity
2
Ethernet LAN (RJ-45) ports
1
HDMI ports quantity
1
HDMI version
2.1
DisplayPorts quantity
2
DisplayPort version
1.4
Headphone outputs
1
Line-in
Yes
WiFi-AP antenna jack
2

Network

Ethernet LAN
Yes
Ethernet interface type
2.5 Gigabit Ethernet
Wi-Fi
Yes
Top Wi-Fi standard
Wi-Fi 6E (802.11ax)
Wi-Fi standards
Wi-Fi 6E (802.11ax)
Bluetooth
Yes
Bluetooth version
5.3

Features

Motherboard chipset
AMD B840
Audio output channels
7.1 channels
Product colour
Black
Component for
PC
Motherboard form factor
micro ATX
Motherboard chipset family
AMD
Power source type
ATX
Windows operating systems supported
Windows 10 x64, Windows 11

Expansion slots

PCI Express x16 (Gen 3.x) slots
2
PCI Express x16 (Gen 4.x) slots
1
Number of M.2 (M) slots
3
1st M.2 largest key size
2280
1st M.2 highest PCI Express generation
4.0
2nd M.2 largest key size
2280
2nd M.2 highest PCI Express generation
4.0
3rd M.2 largest key size
2280
3rd M.2 highest PCI Express generation
3.0

BIOS

BIOS type
UEFI AMI
BIOS memory size
256 Mbit

Weight & dimensions

Width
244 mm
Depth
244 mm

Packaging content

Cables included
SATA
Antenna included
Yes
Screws included
Yes

Other features

Quick installation guide
Yes

Specifications and images: Database Right data-sheet 2026 Icecat. All rights reserved. Supplied as is, without warranty. Specs Icecat · Open Content License

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