MB ASUS PRIME B860-PLUS-CSM B860 LGA1851 4XDDR5DC-8200(OC) HDMI DP 1XPCIE5.0X16 4XSATA3 3XM.2 USB ATX 90MB1KA0-M0EAYC

CPU
Support Intel® Core™ Ultra Processors (Series 2) , LGA1851
Supports Intel® Turbo Boost Technology 2.0 and Intel® Turbo Boost Max Technology 3.0

Chipset
Intel® B860 Chipset

Memory
4 x DIMM slots, max. 256GB, DDR5
Support up to  8666+MT/s (OC),  Non-ECC, Un-buffered ,Clocked Unbuffered DIMM (CUDIMM)
Dual channel memory architecture
DIMM Fit
Supports Intel® Extreme Memory Profile (XMP) memory module
ASUS Enhanced Memory Profile III (AEMP III)

Graphics
1 x DisplayPort
1 x HDMI™ port  

Expansion Slots
Intel® Core™ Ultra Processors (Series 2): 
- 1 x PCIe 5.0 x16 slot
Intel® B860 Chipset: 
- 1 x PCIe 4.0 x16 slot (supports x4 mode)

Storage
Total supports 3 x M.2 slots and 4 x SATA 6Gb/s ports
Intel® Core™ Ultra Processors (Series 2): 
- M.2_1 slot (Key M), type 2242/2260/2280 (supports PCIe 5.0 x4 mode)
Intel® B860 Chipset: 
- M.2_2 slot (Key M), type 2242/2260/2280/22110 (supports PCIe 4.0 x4 mode)
- M.2_3 slot (Key M), type 2242/2260/2280 (supports PCIe 4.0 x4 mode)
- 4 x SATA 6Gb/s ports

Ethernet
1 x Realtek 2.5Gb Ethernet
ASUS LANGuard

Wireless & Bluetooth
M.2 slot only (Key E, CNVi & PCIe)

USB
Rear USB (Total 6 ports): 
- 1 x USB 20Gbps port (1 x USB Type-C®)
- 2 x USB 10Gbps ports (2 x Type-A)
- 1 x USB 5Gbps port (1 x Type-A)
- 2 x USB 2.0 ports (2 x Type-A)
Front USB (Total 7 ports): 
- 1 x USB 5Gbps port (1 x USB Type-C®)
- 1 x USB 5Gbps header supports additional 2 USB 5Gbps ports
- 2 x USB 2.0 headers support 4 additional USB 2.0 ports

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

Back Panel I/O Ports
1 x USB 20Gbps port (1 x USB Type-C®)
2 x USB 10Gbps ports (2 x Type-A)
1 x USB 5Gbps port (1 x Type-A)
2 x USB 2.0 ports (2 x Type-A)
1 x DisplayPort
1 x HDMI™ port
1 x Realtek 2.5Gb Ethernet port
3 x Audio jacks

Internal I/O Connectors
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
- 4 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 header support 4 additional USB 2.0 ports
Miscellaneous: 
- 3 x Addressable Gen 2 headers
- 1 x Aura RGB header
- 1 x Clear CMOS header
- 1 x Chassis Intrusion 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 (14-1pin)
- 1 x 10-1 pin Front System Panel header
- 1 x Thunderbolt™ (USB4®) header

Special Features
ASUS 5X PROTECTION III: 
-DIGI+ VRM (- Digital power design with DrMOS)
- LANGuard
- Overvoltage Protection
- SafeSlot
- Stainless-steel back I/O
ASUS Q-Design: 
- Q-Dashboard
- Q-DIMM
- Q-LED (CPU [red], DRAM [yellow], VGA [white], Boot Device [yellow green])
- Q-Slot
ASUS Thermal Solution: 
- Flexible M.2 heatsink
- VRM heatsink design
ASUS EZ DIY: 
- ProCool
- Pre-mounted I/O shield
Aura Sync: 
- Aura RGB header
- Addressable Gen 2 headers

Software Features
ASUS Exclusive Software: 
Armoury Crate
- Aura Creator
- Aura Sync
- Fan Xpert 2+
- Power Saving
ASUS AI Advisor
ASUS DriverHub
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
- ASUS UEFI BIOS EZ Mode
- ASUS MyHotkey

BIOS
2 x 128 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
- 1 x Screw package for M.2 Key E
Documentation: 
- 1 x Quick start guide
Cables: 
- 2 x SATA 6Gb/s cables
Miscellaneous: 
- 1 x M.2 rubber package
- 2 x Screw packages for M.2 SSD
- 1 x Screw package for M.2 Key E
Documentation: 
- 1 x ACC Express Activation Key Card
- 1 x Quick start guide

Operating System
Windows 11 (22H2 & later), Windows 10 64-bit (21H2 & later)

Form Factor
ATX Form Factor
12 inch x 9.6 inch (30.5 cm x 24.4 cm)