ASRock B850 Pro-A AMD AM5 Socket Motherboard, ATX, 4x DDR5 Slots, 4x M.2 Sockets, 2.5GbE LAN, 1x HDMI Port / 1x USB-C

ASRock B850 PRO A Micro ATX Motherboard (AMD AM5)

ASRock B850 PRO A is a Micro ATX motherboard designed for AMD Socket AM5 Ryzen 9000, 8000 and 7000 Series Processors, combining PCIe Gen5 support, DDR5 performance, rich storage options and robust power delivery.

Key Features

• CPU Support
• Supports AMD Socket AM5 Ryzen 9000, 8000 and 7000 Series Processors

• Integrated AMD RDNA™ graphics support (actual support may vary by CPU)

• Power Design

• 14 + 2 + 1 power phase design
• 80A Dr.MOS for VCore + SOC + MISC

• VCore with Dr.MOS design for smoother, neater power to the CPU

• Memory

• 4 x DDR5 DIMM slots, Dual Channel
• Supports DDR5 ECC/non-ECC, un-buffered memory up to 8000+ (OC)
• Max system memory capacity: 256GB

• Supports XMP and EXPO memory profiles

• Graphics Outputs

• 1 x HDMI 2.1 TMDS/FRL 8G compatible, supports HDR, HDCP 2.3, up to 4K 120Hz

• 1 x USB 3.2 Gen1 Type-C (DP-alt mode), supports DP 1.4 HBR3, up to 4K 60Hz (DP1.4a)

• Expansion Slots

• 1 x PCIe 5.0 x16 (PCIE1, CPU)
• 1 x PCIe 4.0 x16 (PCIE2, Chipset, x4 mode)
• 1 x M.2 Key E (type 2230) for WiFi/BT PCIe module

• 15µ Gold Contact in VGA PCIe Slot (PCIE1)

• High-Speed Storage

• 1 x Blazing M.2 (PCIe Gen5 x4)
• 2 x Hyper M.2 (PCIe Gen4 x4)
• 1 x Ultra M.2 (PCIe Gen3 x4)
• 4 x SATA3 6.0 Gb/s (2 via chipset, 2 via ASMedia ASM1061)
• Supports NVMe SSDs as boot disks

• Supports RAID 0/1 for SATA and RAID 0/1/10 for M.2 NVMe

• USB Connectivity

• 1 x USB 3.2 Gen2x2 Type-C (Front, up to 20 Gb/s)
• 1 x USB 3.2 Gen2 Type-C (Rear)
• 1 x USB 3.2 Gen1 Type-C (Rear, DP-alt mode)
• 6 x USB 3.2 Gen1 Type-A (4 Rear, 2 Front)
• 9 x USB 2.0 (6 Rear, 3 Front)

• All USB ports with ESD protection

• Networking

• Realtek Dragon RTL8125BG 2.5G LAN (10/100/1000/2500 Mb/s)

• Dragon 2.5G LAN Software:

  • Smart Auto Adjust Bandwidth Control
  • Visual Network Usage Statistics
  • Optimized defaults for Game, Browser, and Streaming modes
  • User customized priority control

• Audio

• Realtek ALC897 7.1 CH HD Audio Codec

• HD Audio jacks: Line in / Front Speaker / Microphone

• Convenience & Utilities

• BIOS Flashback support
• ASRock Auto Driver Installer
• EZ Troubleshooter & ASRock Post Status Checker
• ASRock Motherboard Utility (A-Tuning)
• ASRock Dragon 2.5G LAN Software

• ASRock Polychrome SYNC RGB

• Customization & RGB

• 1 x RGB LED header
• 3 x Addressable LED headers
• Supports in total up to:
  • 12V/3A, 36W LED strip
  • 5V/3A, 15W LED strip

• Polychrome SYNC for customizable lighting

• M.2 Key E for WiFi

• M.2 (Key E) slot allows wireless module upgrades

• Front USB 3.2 Gen2x2 Type-C

• Up to 20 Gb/s data transfer rate (2x faster than previous generation)

• USB Type-C (DP-Alt Mode)

• USB Alternate Mode enables data transfer and DisplayPort output through a single USB Type-C cable

Specifications

Platform

CPU

Memory

Expansion Slots

PCIe Lane Behavior

• PCIE1:
• Gen5 x16 with 9000 and 7000 series processors
• Gen4 x8 with 8000 (Phoenix 1) series processors

• Gen4 x4 with 8000 (Phoenix 2) series processors

• If M2_3 is occupied, PCIE2 will be disabled.

Graphics

Audio

LAN

USB

CPU

• 1 x USB 3.2 Gen2 Type-C (Rear)
• 1 x USB 3.2 Gen1 Type-C (Rear)
• 2 x USB 3.2 Gen1 Type-A (Rear, USB32_1 and USB32_2)

Chipset

• 1 x USB 3.2 Gen2x2 Type-C (Front)
• 4 x USB 3.2 Gen1 Type-A (2 Rear: USB32_3 and USB32_4, 2 Front)
• 9 x USB 2.0 (6 Rear, 3 Front)

All USB ports support ESD protection.

Rear Panel I/O

• 2 x Antenna mounting points
• 1 x HDMI port
• 1 x USB 3.2 Gen2 Type-C (10 Gb/s)
• 1 x USB 3.2 Gen1 Type-C (DP-alt mode, DP1.4a)
• 4 x USB 3.2 Gen1 Type-A ports
• 6 x USB 2.0 ports
• 1 x RJ-45 LAN port
• 1 x BIOS Flashback button
• HD Audio jacks (Line in / Front Speaker / Microphone)

Storage

M.2 Lane Behavior

• M2_1:
• Gen5x4 with 9000 and 7000 series processors

• Gen4x4 with 8000 (Phoenix 1 and Phoenix 2) series processors

• M2_2:

• Gen4x4 with 9000 and 7000 series processors
• Gen4x4 with 8000 (Phoenix 1) series processors

• Gen4x2 with 8000 (Phoenix 2) series processors

• If SATA3_1 or SATA3_2 is occupied, M2_4 runs at Gen3x2.

Connectors & Headers

• 1 x SPI TPM header
• 1 x Power LED and speaker header
• 1 x RGB LED header
• 3 x Addressable LED headers
• 2 x CPU fan connectors (4-pin, Smart Fan Speed Control)
• 4 x Chassis fan connectors (4-pin, Smart Fan Speed Control)
• 1 x AIO pump fan connector (4-pin, Smart Fan Speed Control)
• 1 x 24-pin ATX power connector
• 2 x 8-pin 12V power connectors (Hi-Density Power Connector)
• 1 x Front panel audio connector
• 2 x USB 2.0 headers (support 3 USB 2.0 ports)
• 1 x USB 3.2 Gen1 header (supports 2 USB 3.2 Gen1 ports)
• 1 x Front panel Type-C USB 3.2 Gen2x2 header (20 Gb/s)

Fan Power Support

• CPU_FAN1: up to 1A (12W)
• CPU_FAN2, CHA_FAN1–4, AIO_PUMP: up to 3A (36W) each
• CPU_FAN2, CHA_FAN1–4 and AIO_PUMP auto-detect 3-pin/4-pin fans

BIOS

• 256Mb AMI UEFI Legal BIOS with GUI support

Software & UEFI

• Software
• ASRock Motherboard Utility (A-Tuning)
• ASRock Dragon 2.5G LAN Software

• ASRock Polychrome SYNC

• UEFI

• ASRock EZ Mode
• ASRock Full HD UEFI
• ASRock Auto Driver Installer
• ASRock Instant Flash

OS Support

• Microsoft Windows 10 64-bit
• Microsoft Windows 11 64-bit

Certifications

• FCC
• CE
• ErP/EuP ready (ErP/EuP ready power supply required)

Accessories

• 1 x I/O Shield
• 2 x SATA data cables
• 1 x Screw for M.2 socket