ASUS Prime B840M-A WIFI 6E CSM DDR5 AMD Motherboard

The ASUS Prime B840M-A WiFi 6E CSM is a Micro-ATX motherboard built on the AMD B840 chipset with an AM5 socket, designed to support AMD Ryzen 7000, Ryzen 8000, and Ryzen 9000 series desktop processors. It pairs a compact form factor with a solid connectivity suite, making it a practical option for space-conscious builds that still demand modern performance headroom. Memory support is a standout characteristic. The board accepts DDR5 modules in dual-channel configuration, supporting speeds up to 7600+ MT/s with a maximum capacity of 192 GB across its DIMM slots. For users with standard DDR5 kits, ASUS Enhanced Memory Profile (AEMP) automatically detects memory chips and applies optimized profiles. Enthusiasts seeking higher throughput can leverage AMD EXPO (Extended Profiles for Overclocking) alongside additional UEFI tuning options. Storage flexibility is well catered for via three M.2 Key-M slots: two operating at PCIe 4.0 speeds (up to 64 Gbps each) and one via PCIe 3.0, complemented by four SATA 6 Gb/s ports. The primary PCIe 4.0 x16 slot operates at full x16 bandwidth with Ryzen 9000 and 7000 series CPUs, while the B840 chipset contributes two additional PCIe 3.0 x16 slots running at x1 mode. Connectivity on the rear I/O panel includes integrated WiFi 6E and Bluetooth 5.3 via an onboard Wi-Fi module, a Realtek 2.5 Gb Ethernet port, two USB 10 Gbps Type-A ports, one USB 5 Gbps Type-C port, and four USB 2.0 Type-A ports. Video output options cover two DisplayPort outputs and one HDMI port for systems leveraging integrated graphics. A dedicated BIOS FlashBack button enables UEFI updates without a processor or memory installed. For system builders and integrators, the CSM (Compatibility Support Module) designation ensures legacy BIOS compatibility alongside modern UEFI operation — a feature valued in managed IT and commercial deployment scenarios. Internal headers include three Addressable Gen 2 (ARGB) headers, an AIO pump header, three chassis fan headers, a COM port header, an SPI TPM header, and S/PDIF out. Verified Specifications: – Socket: AM5 | Chipset: AMD B840 – CPU Compatibility: Ryzen 7000, Ryzen 8000, Ryzen 9000 series – Form Factor: Micro-ATX – Memory: DDR5 Dual-Channel, up to 7600+ MT/s, max 192 GB – Storage: 3x M.2 (Key-M); 2x PCIe 4.0, 1x PCIe 3.0; 4x SATA 6 Gb/s – Display Output: 2x DisplayPort, 1x HDMI – Networking: WiFi 6E, Bluetooth 5.3, Realtek 2.5 GbE – Rear USB: 2x USB 10 Gbps (Type-A), 1x USB 5 Gbps (Type-C), 4x USB 2.0 – ARGB Headers: 3x Addressable Gen 2 – Warranty: 3 Years