Description

ASUS PRIME B840M-A WIFI AMD B840 Ryzen Socket AM5 Micro-ATX Motherboard

90MB1J20-M0EAY0

ASUS Prime series motherboards are expertly engineered to unleash the full potential of AMD Ryzen 9000 series processors. The PRIME B840M-A WIFI motherboard provides users and PC DIY builders with a range of performance optimisations 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.

• AMD Socket AM5 for AMD Ryzen™ 9000 & 8000 & 7000 Series Desktop Processors.
• AMD B840 Chipset.
• 4x DIMM slots, max. 192GB, DDR5.
• 1x PCIe 4.0 x16 slot (supports x16 mode).
• Wi-Fi 6E.
• Realtek 7.1 Surround Sound High Definition Audio.
• Micro-ATX Form Factor.

AI Advisor

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

Digital Power Design

PRIME B840M-A WIFI 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.

Multi-Layered Printed Circuit Board

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.

Power Saving Function

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.

Digi+ Voltage-Regulator

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

Enhanced DDR5 Performance

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

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

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

Three M.2 Slots (up to 64 Gbps)

PRIME B840M-A WIFI 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.

VRM Heatsink and Thermal Pads

Massive VRM heatsink and essential thermal pads improve heat transfer from the MOSFETs and chokes for better cooling performance.

Multiple Temperature Sources

Each header can dynamically reference three thermal sensors. Fan Xpert 2+ lets you to map the temperature of supported ASUS graphics cards to optimize cooling for GPU- and CPU-intensive tasks.

M.2 Heatsink

One M.2 heatsink takes care of the M.2 slot, preventing throttling that can occur with M.2 storage during extended transfers.

Passive Chipset Heatsink

An aluminium passive chipset heatsink ensures optimal cooling and stable performance. It is more durable and longer-lasting than heatsinks with fans, which can be vulnerable to the buildup of dust and debris.

Smart Protection

A dedicated integrated circuit protects each fan header from overheating and excess current.

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.

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.

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.

Built-in WiFi 6E

Built-in WiFi 6E 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.

Personalisation

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

Aura Sync

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

SPECIFICATIONS
Brand	ASUS
Series	PRIME
Model	PRIME B840M-A WIFI
CPU	AMD Socket AM5 for AMD Ryzen 9000 & 8000 & 7000 Series Desktop Processors*
Memory	4 x DIMM slots, max. 192GB, DDR5
	Support up to 7600+MT/s (OC) with Ryzen 9000 & 8000 & 7000 Series Processors, ECC and Non-ECC, Un-buffered DIMM*
	Dual channel memory architecture
	Supports 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/.
	* Non-ECC, un-buffered DDR5 memory supports On-Die ECC function.
Graphics	2 x DisplayPort**
	1 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 Processors
	1 x PCIe 4.0 x16 slot (supports x8/x4 mode)
	AMD B840 Chipset
	2 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 ports*
	AMD Ryzen 9000 & 8000 & 7000 Series Desktop Processors
	M.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 B840 Chipset
	M.2_3 slot (Key M), type 2280 (supports PCIe 3.0 x4 mode)
	4 x SATA 6Gb/s ports
	* AMD RAIDXpert2 Technology supports both PCIe RAID 0/1/5/10 and SATA RAID 0/1/5/10. RAID 5 Function is only supported by AMD Ryzen 9000 series CPU.
Ethernet	1 x Realtek 2.5Gb Ethernet
	ASUS LANGuard
Wireless & Bluetooth	Wi-Fi 6E
	2×2 Wi-Fi 6E (802.11ax)
	Supports 2.4/5/6GHz frequency band*
	Bluetooth v5.3**
	* WiFi 6E 6GHz regulatory may vary between countries, supported only in Windows 11 or later.
	** The Bluetooth version may vary, please refer to the Wi-Fi module manufacturer’s website for the latest specifications.
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 ports
	2 x USB 2.0 headers support 4 additional USB 2.0 ports
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 playback
	Audio 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 DisplayPort
	1 x HDMI port
	1 x Wi-Fi module
	1 x Realtek 2.5Gb Ethernet port
	3 x Audio jacks
	1 x BIOS FlashBack button
Internal I/O Connectors	Fan and Cooling Related
	1 x 4-pin CPU Fan header
	1 x 4-pin CPU OPT Fan header
	1 x 4-pin AIO Pump header
	3 x 4-pin Chassis Fan headers
	Power Related
	1 x 24-pin Main Power connector
	1 x 8-pin +12V CPU Power connector
	Storage Related
	3 x M.2 slots (Key M)
	4 x SATA 6Gb/s ports
	USB
	1 x USB 5Gbps connector (supports USB Type-C )
	1 x USB 5Gbps header supports 2 additional USB 5Gbps ports
	2 x USB 2.0 headers support 4 additional USB 2.0 ports
	Miscellaneous
	3 x Addressable Gen 2 headers
	1 x Clear CMOS header
	1 x COM Port header
	1 x Front Panel Audio header (F_AUDIO)
	1 x S/PDIF Out header
	1 x SPI TPM header (14-1 pin)
	1 x 10-1 pin Front System Panel header
Special Features	ASUS 5X PROTECTION III
	– DIGI+ VRM
	– LANGuard
	– Overvoltage protection
	– SafeSlot Core+
	– Stainless-steel back I/O
	ASUS Q-Design
	– Q-Antenna
	– Q-Dashboard
	– Q-DIMM
	– Q-LED Core
	– Q-Slot
	ASUS Thermal Solution
	– M.2 heatsink
	– VRM heatsink design
	ASUS EZ DIY
	– BIOS FlashBack button
	– BIOS FlashBack LED
	– Pre-mounted I/O shield
	Aura Sync
	– Addressable Gen 2 headers
Software Features	ASUS Exclusive Software
	Armoury Crate
	– Aura Creator
	– Aura Sync
	– Fan Xpert 2+
	– Power Saving
	ASUS DriverHub
	ASUS GlideX
	TurboV Core
	ASUS CPU-Z
	Norton 360 Deluxe (60 Days Free Trial)
	WinRAR (40 Days Free Trial)
	UEFI BIOS
	ASUS EZ DIY
	– ASUS CrashFree BIOS 3
	– ASUS EZ Flash 3
	– ASUS UEFI BIOS EZ Mode
	– ASUS MyHotkey
BIOS	256 Mb Flash ROM, UEFI AMI BIOS
Form Factor	micro-ATX Form Factor
	9.6 inch x 9.6 inch (24.4 cm x 24.4 cm)
Warranty Information
Warranty	3 Year Warranty