ASUS Prime B840M-A CSM DDR5 AMD Motherboard
Features of ASUS Prime B840M-A CSM DDR5 AMD Motherboard
PRIME B840M-A-CSM
ASUS Prime series motherboards are expertly engineered to unleash the full potential of AMD Ryzen™ 9000 series processors. The PRIME B840M-A-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.
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.
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-CSM 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-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.
Cooler by design
The PRIME B840M-A-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.
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 PCIe 4.0 slot and an arsenal of USB ports which includes Type-C® connections.
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.
Personalization
The PRIME B840M-A-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.
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.
Specifications of ASUS Prime B840M-A CSM DDR5 AMD Motherboard
| Model | PRIME B840M-A-CSM |
| CPU | AMD Socket AM5 for AMD Ryzen™ 9000 & 8000 & 7000 Series Desktop Processors* |
| Chipset | AMD B840 Chipset |
| Memory | 4 x DIMM slots, max. 192GB, DDR5 Supports 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. |
| 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 & 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 |
| Ethernet | 1 x Realtek 2.5Gb Ethernet ASUS LANGuard |
| 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 * USB Type-C® power delivery output: max. 5V/3A |
| 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 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 2 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 |
| Special Features | ASUS 5X PROTECTION III – DIGI+ VRM – LANGuard – Overvoltage protection – SafeSlot Core+ – Stainless-steel back I/O ASUS Q-Design – 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 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 |
| Remote Management Features | IT Management software supported – ASUS Control Center Express (ACCE) |
| BIOS | 256 Mb Flash ROM, UEFI AMI BIOS |
| Manageability | WOL by PME, PXE |
| Accessories | Cables 2 x SATA 6Gb/s cables Miscellaneous 1 x M.2 rubber package 2 x Screw packages for M.2 SSD Documentation 1 x ACC Express Activation Key Card 1 x Quick start guide |
| Operating System | Windows 11, Windows 10 64-bit |
| Form Factor | micro-ATX Form Factor 9.6 inch x 9.6 inch (24.4 cm x 24.4 cm) |
| Warranty | 3 Years |
| Note** | **Prices, Specifications & Features are subject to change without notice |
$63.29
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-65%ASUS Prime B840M-A CSM DDR5 AMD Motherboard—
$180.82
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Description
Features of ASUS Prime B840M-A CSM DDR5 AMD Motherboard
PRIME B840M-A-CSM
ASUS Prime series motherboards are expertly engineered to unleash the full potential of AMD Ryzen™ 9000 series processors. The PRIME B840M-A-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.
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.
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-CSM 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-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.
Cooler by design
The PRIME B840M-A-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.
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 PCIe 4.0 slot and an arsenal of USB ports which includes Type-C® connections.
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.
Personalization
The PRIME B840M-A-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.
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.
Specifications of ASUS Prime B840M-A CSM DDR5 AMD Motherboard
| Model | PRIME B840M-A-CSM |
| CPU | AMD Socket AM5 for AMD Ryzen™ 9000 & 8000 & 7000 Series Desktop Processors* |
| Chipset | AMD B840 Chipset |
| Memory | 4 x DIMM slots, max. 192GB, DDR5 Supports 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. |
| 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 & 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 |
| Ethernet | 1 x Realtek 2.5Gb Ethernet ASUS LANGuard |
| 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 * USB Type-C® power delivery output: max. 5V/3A |
| 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 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 2 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 |
| Special Features | ASUS 5X PROTECTION III – DIGI+ VRM – LANGuard – Overvoltage protection – SafeSlot Core+ – Stainless-steel back I/O ASUS Q-Design – 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 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 |
| Remote Management Features | IT Management software supported – ASUS Control Center Express (ACCE) |
| BIOS | 256 Mb Flash ROM, UEFI AMI BIOS |
| Manageability | WOL by PME, PXE |
| Accessories | Cables 2 x SATA 6Gb/s cables Miscellaneous 1 x M.2 rubber package 2 x Screw packages for M.2 SSD Documentation 1 x ACC Express Activation Key Card 1 x Quick start guide |
| Operating System | Windows 11, Windows 10 64-bit |
| Form Factor | micro-ATX Form Factor 9.6 inch x 9.6 inch (24.4 cm x 24.4 cm) |
| Warranty | 3 Years |
| Note** | **Prices, Specifications & Features are subject to change without notice |
