ASUS PRIME B860M-A-CSM – LGA1851 Socket & DDR5 8666+ MT/s — PCIe 5.0 x16, 2x M.2 Slots (1x Gen5) & USB 20Gbps Type-C

CPU & Chipset

• CPU Socket: Intel® LGA1851
• Supported Processors: Intel® Core™ Ultra Processors (Series 2)
• Chipset: Intel® B860
• Technologies Supported: Intel® Turbo Boost Technology 2.0, Intel® Turbo Boost Max Technology 3.0 (CPU dependent)

Memory

• Memory Type: DDR5
• Memory Slots: 4 × DIMM slots
• Maximum Capacity: 256 GB
• Supported Speeds: Up to 8666+ MT/s (O.C.)
• Memory Architecture: Dual-channel
• Supported Features: Non-ECC, Un-buffered, Clocked Unbuffered DIMM (CUDIMM), On-Die ECC function, Intel® Extreme Memory Profile (XMP), ASUS Enhanced Memory Profile III (AEMP III)

Expansion Slots

• PCIe x16 (CPU): 1 × PCIe 5.0 x16 slot
• PCIe x16 (Chipset): 1 × PCIe 4.0 x16 slot (supports x4 mode)
• PCIe x1 (Chipset): 1 × PCIe 4.0 x1 slot

Storage Interfaces

• M.2 Slots: 2 × M.2 slots (Key M)
  • M.2_1 (CPU lanes): Supports type 2242/2260/2280, PCIe 5.0 x4 mode
  • M.2_2 (Chipset lanes): Supports type 2242/2260/2280, PCIe 4.0 x4 mode
• SATA Ports: 4 × SATA 6Gb/s ports
• RAID Support: Intel® Rapid Storage Technology supports SATA RAID 0/1/5/10

Audio & Networking

• Audio CODEC: Realtek 7.1 Surround Sound High Definition Audio CODEC
• Audio Features: Supports up to 24-Bit/192 kHz playback, Jack-detection, Multi-streaming, Front Panel Jack-retasking, Audio Shielding, Premium audio capacitors, Dedicated audio PCB layers
• LAN: Realtek 2.5Gb Ethernet with ASUS LANGuard (Surge protection)

USB Connectivity

• Rear Panel (Total 8 ports):
  • 1 × USB 20Gbps port (1 × USB Type-C® with DisplayPort Alt mode)
  • 1 × USB 10Gbps port (1 × Type-A)
  • 2 × USB 5Gbps ports (2 × Type-A)
  • 4 × USB 2.0 ports (4 × Type-A)
• Internal Headers (Total 5 ports):
  • 1 × USB 10Gbps connector (supports USB Type-C® with max 5V/3A power delivery)
  • 1 × USB 5Gbps header (supports 2 additional Type-A ports)
  • 1 × USB 2.0 header (supports 2 additional Type-A ports)

Back Panel I/O Ports

• 1 × USB 20Gbps port (USB Type-C® with DP Alt mode)
• 1 × USB 10Gbps port (Type-A)
• 2 × USB 5Gbps ports (Type-A)
• 4 × USB 2.0 ports (Type-A)
• 2 × DisplayPort
• 1 × HDMI™ port
• 1 × Realtek 2.5Gb Ethernet port
• 3 × Audio jacks

Internal I/O Connectors

• Fan & Cooling:
  • 1 × 4-pin CPU Fan header
  • 1 × 4-pin CPU OPT Fan header
  • 1 × 4-pin AIO Pump header
  • 3 × 4-pin Chassis Fan headers
• Power:
  • 1 × 24-pin Main Power connector
  • 1 × 8-pin +12V CPU Power connector
• Storage:
  • 2 × M.2 slots (Key M)
  • 4 × SATA 6Gb/s ports
• USB Headers:
  • 1 × USB 10Gbps connector (Type-C®)
  • 1 × USB 5Gbps header
  • 1 × USB 2.0 header
• RGB Lighting:
  • 3 × Addressable Gen 2 headers
  • 1 × Aura RGB header
• Miscellaneous:
  • 1 × Clear CMOS header
  • 1 × Chassis Intrusion header
  • 1 × COM Port header
  • 1 × Front Panel Audio header (F_AUDIO)
  • 1 × S/PDIF Out header
  • 1 × SPI TPM header (14-1 pin)
  • 1 × 10-1 pin Front System Panel header
  • 1 × Thunderbolt™ (USB4®) header

Special Features

• ASUS 5X PROTECTION III:
  • DIGI+ VRM (Digital power design with DrMOS)
  • ESD Guards
  • LANGuard
  • Overvoltage protection
  • SafeSlot
  • Stainless-steel back I/O
• ASUS Q-Design:
  • Q-Dashboard (UEFI BIOS overview)
  • Q-DIMM (Single-sided clips for easy RAM installation)
  • Q-LED Core (Troubleshooting indicators)
  • Q-Slot (Easy PCIe device installation)
• ASUS Thermal Solution:
  • M.2 heatsink
  • VRM heatsink design
• ASUS EZ DIY:
  • ProCool (Solid pins for better power contact)
  • Pre-mounted I/O shield
• Aura Sync:
  • Full RGB synchronization support via headers

Physical Specifications & Compatibility

• Form Factor: Micro-ATX (9.6 inch × 9.6 inch / 24.4 cm × 24.4 cm)
• Operating System Support: Windows® 11 64-bit