PRIME B850M-K

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AMD Socket AM5 for AMD Ryzen^™ 9000 & 8000 & 7000 Series Desktop Processors*
* Refer to https://www.asus.com/support/download-center/ for CPU support list.

AMD B850 Chipset

2 x DIMM slots, max. 128GB, DDR5 Supports up to
8200+MT/s(OC) with Ryzen^™ 9000 Series Processors,
9600+MT/s(OC) with Ryzen^™ 8000 Series Processors,
8000+MT/s(OC) with Ryzen^™ 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.

1 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.

AMD Ryzen™ 9000 & 7000 Series Desktop Processors*
1 x PCIe 5.0 x16 slot (supports x16 mode)
AMD Ryzen™ 8000 Series Desktop Processors
1 x PCIe 4.0 x16 slot (supports x8/x4 mode)**
AMD B850 Chipset
1 x PCIe 4.0 x16 slot (support x4 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

Supports 2 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 5.0 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 B850 Chipset
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

1 x Realtek 2.5Gb Ethernet
ASUS LANGuard

Rear USB (Total 8 ports)
2 x USB 10Gbps ports (2 x Type-A)
2 x USB 5Gbps ports (2 x Type-A)
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

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.

2 x USB 10Gbps ports (2 x Type-A)
2 x USB 5Gbps ports (2 x Type-A)
4 x USB 2.0 ports (4 x Type-A)
1 x DisplayPort
1 x HDMI^™ port
1 x Realtek 2.5Gb Ethernet port
3 x Audio jacks
1 x BIOS FlashBack^™ button
1 x PS/2 Keyboard/Mouse combo port

Fan and Cooling Related
1 x 4-pin CPU Fan header
3 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
2 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 RGB 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 System Panel header

ASUS 5X PROTECTION III
- DIGI+ VRM
- LANGuard
- Overvoltage protection
- SafeSlot
- 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
- SafeSlot
Aura Sync
- Addressable RGB Gen 2 headers

ASUS Exclusive Software
Armoury Crate
- Aura Creator
- Aura Sync
- Fan Xpert 2+
ASUS AI Advisor
ASUS DriverHub
TurboV Core
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 3
- ASUS UEFI BIOS EZ Mode
- ASUS MyHotkey

256 Mb Flash ROM, UEFI AMI BIOS

WOL by PME, PXE

Cables
2 x SATA 6Gb/s cables
Miscellaneous
1 x I/O Shield
1 x M.2 rubber package
1 x Screw package for M.2 SSD
Documentation
1 x Quick start guide

Windows^® 11, Windows^® 10 64-bit

micro-ATX Form Factor
9.6 inch x 8.7 inch ( 24.4 cm x 22.1 cm )