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

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

ASUS Corporate Stable Model
ASUS Corporate Stable Model (CSM) is a commercial program designed to provide stable and reliable motherboards. We offer up to 36-month product lifecycle support and a 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.
Learn more about the ASUS CSM Program
* Lifecycle support, program offering, and supply status may vary by region. Please contact your local sales representative for more information.

ASUS Control Center Express
ASUS Control Center Express is integrated IT monitoring and management software designed to speed up deployment, simplify IT operations, and enhance 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 business needs.

Optimize IT Endpoint Management
Designed to assist IT staff in monitoring and controlling devices within their corporate networks, and facilitate inventory checking at 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 hours, enhancing system stability and IT operational flexibility

Securely Manage All 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 a technical expert with knowledge of PC performance.

AI Advisor
The ASUS AI Advisor allows users to explore the features and advanced capabilities of ASUS motherboards in a simple and straightforward manner.7

Performance
Digital Power Design
The PRIME B840M-A-CSM features an 8+2+1 phase power design with discrete MOSFETs to provide efficient and stable power delivery to AMD processors, as well as consistent performance for everyday use.5

Multi-layered 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 various settings to optimize power consumption and maximize energy savings. You can enable a CPU power limit, dim the Aura lighting, and set the fan profile to a power saving mode. You can also toggle the power plan integrated into Microsoft Windows.

The Digi+ Voltage Regulator Module (VRM) provides real-time control over voltage drop and automatically controls 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-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 the memory chips and offers optimized profiles for improved performance.
For those who want to exceed standard DDR5 speeds, the PRIME B840M-A-CSM offers extensive AMD Extended Profiles for Overclocking (EXPO™) support and a wide range of UEFI settings for further performance enhancements.3

Three M.2 Slots (up to 64 Gbps)
The PRIME B840M-A-CSM offers a total of three M.2 slots, two of which support data transfer speeds of up to 64 Gbps via PCIe 4.0 and one PCIe 3.0. This allows for faster boot and load times for operating systems and applications.4

Cooling
Cooler by Design
The PRIME B840M-A-CSM motherboard is equipped with multiple onboard heatsinks and a range of hybrid fan headers to ensure your system stays cool and stable even under heavy loads.

Intelligent Cooling Precision

ASUS Fan Xpert 2+
ASUS Fan Xpert 2+ software provides comprehensive control over fans. Auto-Tuning mode intelligently configures all parameters with a single click. There is also an ultra-quiet mode that reduces fan speeds below the standard minimum, keeping your system whisper-quiet during light tasks. Fans can also be controlled via the UEFI BIOS.5

Cooler Compatibility
ASUS AIO coolers offer robust performance, high overclocking potential, striking aesthetics, and customizable features for new motherboards, allowing you to build your dream gaming rig.5

Flexibility
Stronger Connections
This motherboard offers versatile connectivity, including support for PCIe 4.0 slots and a whole arsenal of USB ports, including Type-C® ports.

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

Front USB 5Gbps Type-C®
This motherboard features a front USB 5Gbps Type-C® port for fast data transfers of up to 5Gbps.5

Customization
Personalization
The PRIME B840M-A-CSM enhances the user experience in all areas, from simplifying BIOS settings to customizable RGB lighting control for a truly personal system aesthetic.

UEFI BIOS
The UEFI interface offers user-friendly configuration options for PC novices and advanced features for veterans.

ASUS DriverHub
Simplify driver management with automatic detection, one-click installation, and updates 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 the number of LEDs on compatible RGB devices and automatically adjust lighting effects.

Customization
DIY-Friendly
The PRIME B840M-A-CSM motherboard features EZ PC DIY innovations that simplify and accelerate the PC building process, making DIY easy and convenient.

Pre-mounted I/O Shield
Our pre-installed I/O shield protects ports, simplifies assembly, increases functionality, and enhances aesthetics for PC DIY enthusiasts.

BIOS FlashBack™
BIOS FlashBack™ simplifies BIOS updates. Simply download the BIOS file to a FAT32 USB stick, plug it into the BIOS FlashBack™ port, and press a button - no CPU or memory required.

SafeSlot Core+
SafeSlot Core+ is a one-piece stainless steel brace that protects the slot from damage. The metal cover is firmly secured in the slot with hooks, and the entire assembly is firmly anchored to the board with reinforced solder points to provide a secure foundation for heavy-duty graphics cards.

Q-LED Core
The Q-LED Core display shows colored lights during power-on self-test (POST) that can help you troubleshoot.

Engineered for the Most Advanced Gaming and Creation PC
When it comes to speed, ASUS motherboards are the first choice. With support for faster dual-channel DDR5 memory, AMD EXPO™ technology, and PCIe® 4.0 support for graphics and NVMe, you can play the most demanding games and realize your biggest projects with the revolutionary performance of an ASUS motherboard and AMD Ryzen™ 9000, 8000, and 7000 series processors.