| General |
| Brand |
ASUS |
| Model |
PRIME B840M-A-CSM |
| Part Number |
90MB1J10-M0EAYC |
| Series |
PRIME / CSM |
| Product Type |
Motherboard |
| Processor & Chipset |
| Socket |
AMD AM5 |
| Supported CPUs |
AMD Ryzen 9000 / 8000 / 7000 Series (up to 170W) |
| Chipset |
AMD B840 |
| Memory |
| Memory Slots |
4x DDR5 DIMM, dual channel |
| Max Memory |
256GB |
| Memory Speed |
Up to 7600+ MT/s (OC) |
| Memory Support |
ECC / non-ECC unbuffered, EXPO, AEMP |
| Expansion & Storage |
| PCIe Slots (CPU) |
1x PCIe 4.0 x16 (x16; x8/x4 with Ryzen 8000) |
| PCIe Slots (Chipset) |
2x PCIe 3.0 x16 (x1 mode) |
| M.2 Slots |
M.2_1 2280 PCIe 4.0 x4; M.2_2 PCIe 4.0 x4; M.2_3 2280 PCIe 3.0 x4 |
| SATA |
4x SATA 6Gb/s |
| RAID |
RAID 0/1/5/10 (Ryzen 9000), 0/1 (Ryzen 8000), 0/1/10 (Ryzen 7000) |
| Connectivity |
| Ethernet |
Realtek 2.5Gb, ASUS LANGuard |
| Video Outputs |
2x DisplayPort 1.4 (up to 8K@30Hz), 1x HDMI 2.1 (4K@60Hz) |
| Ports & Connectors |
| Rear USB |
2x USB 10Gbps Type-A, 1x USB 5Gbps Type-C, 4x USB 2.0 Type-A |
| Front USB |
1x USB 5Gbps Type-C connector, 1x USB 5Gbps header (2 ports), 2x USB 2.0 headers (4 ports) |
| Rear I/O Extras |
BIOS FlashBack button, 3x audio jacks |
| Internal Connectors |
COM, S/PDIF out, SPI TPM, Clear CMOS |
| Fan Headers |
CPU, CPU OPT, 2x chassis (4-pin) |
| Power Connectors |
1x 24-pin, 1x 8-pin +12V |
| RGB Headers |
3x Addressable Gen 2 |
| Audio |
| Audio Codec |
Realtek 7.1 HD audio codec, up to 24-bit/192kHz |
| Features & BIOS |
| Power Design |
DIGI+ VRM, ASUS 5X Protection III |
| Cooling |
M.2 heatsink, VRM heatsink |
| Remote Management |
ASUS Control Center Express, WOL, PXE |
| BIOS |
256Mb flash ROM, UEFI AMI BIOS |
| OS Support |
Windows 11, Windows 10 64-bit |
| Physical & Warranty |
| Form Factor |
Micro-ATX |
| Dimensions |
24.4 x 24.4 cm (9.6 x 9.6 in) |
| Warranty |
Official ASUS warranty |
