MAINBOARD (AM5) ASUS PRIME B840M-A WIFI-CSM DDR5

PRIME B840M-A WIFI-CSM (DDR5)

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.

AMD

AM5

AMD B840

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/. 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.

7600

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.

N/A

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.

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.

PCIe 4.0

Total supports 3 x M.2 slots and 4 x SATA 6Gb/s ports

AMD Ryzen™ 9000 & 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 Ryzen™  8000 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/x2 mode)*

AMD B840 Chipset
M.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 Technology
Ryzen™ 9000 Series Processors: RAID 0/1/5/10
Ryzen™ 8000 Series Processors: RAID 0/1
Ryzen™ 7000 Series Processors: RAID 0/1/10

NVMe

3

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

* USB Type-C® power delivery output: max. 5V/3A

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 Panel System header

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

1 x Realtek 2.5Gb Ethernet
ASUS LANGuard

Wi-Fi 6E
2x2 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.

Micro ATX

N/A

256 Mb Flash ROM, UEFI AMI BIOS

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

ASUS Exclusive Software
Armoury Crate
- Aura Creator
- Aura Sync
- Fan Xpert 2+
- Power Saving
ASUS DriverHub
ASUS GlideX
TurboV Core 
ASUS CPU-Z
Adobe Creative Cloud (Free Trial)
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

Windows 11, Windows 10 64-bit

2 x SATA 6Gb/s cables 
1 x ASUS WiFi Q-Antenna
1 x M.2 rubber package
2 x Screw packages for M.2 SSD
1 x Quick start guide