ASUS PRIME B840M-A WIFI-CSM motherboard AMD B840 Socket

Internal I/O
Number of M.2 (M) slots	3
USB 3.2 Gen 2 (3.1 Gen 2) connectors	0
Front panel connector	Yes
Supported storage drive interfaces	M.2, SATA III
USB 2.0 connectors	2
USB 3.2 Gen 1 (3.1 Gen 1) connectors	2
mSATA ports quantity	0
TPM connector	Yes
S/PDIF out connector	Yes
Number of SATA III connectors	4
Number of SATA II connectors	0
Number of SATA connectors	0
Number of COM connectors	1
Number of chassis fan connectors	3
Front panel audio connector	Yes
EPS power connector (8-pin)	Yes
CPU fan connector	Yes
ATX Power connector (24-pin)	Yes
RGB LED pin header	Yes
Number of CPU fan connectors	2
Number of EPS power connectors (8-pin)	1
Number of water pump connectors	1
Number of RGB LED pin headers	3
Performance
Number of HDDs supported	4
Supported storage drive types	HDD & SSD
Component for	PC
Motherboard chipset family	AMD
Motherboard chipset	AMD B840
Motherboard form factor	micro ATX
Audio output channels	7.1 channels
Supported processor sockets	Socket AM5
RAID levels	0, 1, 5, 10
Windows operating systems supported	Windows 10 x64, Windows 11
Processor
Processor manufacturer	AMD
Compatible processor series	AMD Ryzen 7000 Series, AMD Ryzen 8000 Series, AMD Ryzen 9000 Series
Processor socket	Socket AM5
Supported processor sockets	Socket AM5
Memory
Number of memory slots	4
Supported memory types	DDR5-SDRAM
Memory slots type	DIMM
Memory channels	Dual-channel
Maximum internal memory	192 GB
Unbuffered memory	Yes
Supported memory clock speed (max)	7600 MHz
ECC �ompatibility	ECC & Non-ECC
Storage controllers
Number of HDDs supported	4
Supported storage drive types	HDD & SSD
Supported storage drive interfaces	M.2, SATA III
RAID levels	0, 1, 5, 10
Number of storage drives supported	7
RAID support	Yes
Graphics
Parallel processing technology support	Not supported
On-board graphics card	No
Maximum resolution	7680 x 4320 pixels
Rear panel I/O ports
USB 3.2 Gen 1 (3.1 Gen 1) Type-A ports quantity	0
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
USB 3.2 Gen 2 (3.1 Gen 2) Type-C ports quantity	0
DisplayPort version	1.4
USB 2.0 ports quantity	4
Ethernet LAN (RJ-45) ports	1
WiFi-AP antenna jack	2
VGA (D-Sub) ports quantity	0
Headphone outputs	1
HDMI version	2.1
HDMI ports quantity	1
DVI-D ports quantity	0
DisplayPorts quantity	2
Line-in	Yes
Network
Ethernet LAN	Yes
Wi-Fi	Yes
Wi-Fi standards	Wi-Fi 6E (802.11ax)
Ethernet interface type	2.5 Gigabit Ethernet
Bluetooth	Yes
Bluetooth version	5.3
Top Wi-Fi standard	Wi-Fi 6E (802.11ax)
Features
Power source type	ATX
Component for	PC
Motherboard chipset family	AMD
Motherboard chipset	AMD B840
Motherboard form factor	micro ATX
Audio output channels	7.1 channels
Supported processor sockets	Socket AM5
Windows operating systems supported	Windows 10 x64, Windows 11
Product colour	Black
Expansion slots
Number of M.2 (M) slots	3
PCI Express x16 (Gen 3.x) slots	2
PCI Express x16 (Gen 4.x) slots	1
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
Power
Power source type	ATX
Weight & dimensions
Width	244 mm
Depth	244 mm
Packaging content
Quick installation guide	Yes
Cables included	SATA
Screws included	Yes
Antenna included	Yes
Other features
mSATA ports quantity	0
Quick installation guide	Yes

---

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 Â® 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 Â®
This motherboard features a USB 5Gbps Type-C Â® 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 Â® 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.