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Asrock B850 Pro-A (Socket AM5) DDR5 ATX Motherboard
MotherboardsASRock

Asrock B850 Pro-A (Socket AM5) DDR5 ATX Motherboard

MPN: 90-MXBQM0-A0UAYZ

Key specifications

SocketAM5
Form factorATX
ChipsetAMD B850
Memory typeDDR5
M.2 slots5
Max Memory256 GB
Best indexed price
£136.99GBP
Indexed 16 Mar 2026 — verify at retailer. How we get prices

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eBay UK£136.99
Indexed 16 Mar 2026New · seller laptopoutletdirect
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Indexed 20 Oct 2026New
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Full Specifications109 fields

Additional Information

Model Number
90-MXBQM0-A0UAYZ
Gtin
4711581490185

Additional Specifications

Water Cooled
No
Cooling
Passive Heatsinks
Qpi Speed
N/A
Dimensions
305 x 244 mm
Note
-

BIOS

Bios Type
UEFI AMI
Bios Memory Size
256 Mbit

Core Specifications

Edition
B850 Pro-A
Form Factor
ATX
Chipset
AMD B850

Expansion slots

Pci Express X16 Gen 4 X Slots
1
Pci Express X16 Gen 5 X Slots
1
Number Of M 2 M Slots
4
1st M 2 Largest Key Size
2280
1st M 2 Highest Pci Express Generation
5.0
2nd M 2 Largest Key Size
2280
2nd M 2 Highest Pci Express Generation
4.0
3rd M 2 Largest Key Size
2280
3rd M 2 Highest Pci Express Generation
4.0
4th M 2 Largest Key Size
2280
4th M 2 Highest Pci Express Generation
3.0

External Connectivity

Network Interface Type
Wired 2.5 Gigabit LAN
Network Chip Modules
1 x Realtek RTL8125BG
Rear I O Connectors
1 x BIOS Flashback Button 1 x Front Speaker Out 1 x HDMI 2.1 1 x Line In 1 x Mic-In 1 x RJ-45 6 x USB 2.0 4 x USB 3.2 Gen1 Type-A 1 x USB 3.2 Gen1 Type-C / DP 1 x USB 3.2 Gen2 Type-C

Features

Motherboard Chipset
AMD B850
Audio Chip
Realtek ALC897
Audio Output Channels
7.1 channels
Product Colour
Black
Component For
PC
Motherboard Form Factor
ATX
Motherboard Chipset Family
AMD
Windows Operating Systems Supported
Windows 10 x64, Windows 11 x64
Certification
FCC, CE, ErP/EuP

Graphics

Parallel Processing Technology Support
Not supported
Maximum Resolution
3840 x 2160 pixels
Hdcp
Yes

Graphics Support

Primary Gpu Interface
PCIe 5.0 (x16)
Nvidia Sli Support
N/A
Amd Crossfire Support
N/A
Integrated Graphics
Requires Processor Graphics or Discrete GPU
On Board Graphics Connectors
HDMI 2.1 USB Type-C (DisplayPort)

Internal Connectivity

Expansion Slots
1 x M.2 Key E (Supports Wi-Fi modules) 1 x M.2, 22-30/42/60/80, PCIe Gen4x4 1 x M.2, 22-80, PCIe Gen3x4 1 x M.2, 22-80, PCIe Gen4x4 1 x M.2, 22-80, PCIe Gen5x4 1 x PCIe 4.0 x16 (x4 Bandwidth) 1 x PCIe 5.0 x16 4 x SATA 6GB/s
Sata Support
SATA3
Raid Support Via
-
Storage Mode Support
RAID 0 RAID 1 RAID 10
Internal I O
1 x 24-pin (Power) 1 x 4-pin AIO Pump Connector 4 x 4-pin CHA_FAN connector 2 x 8-pin (Power) 3 x Addressable Digital RGB Header 2 x CPU Fan Connector 1 x Front Panel Audio Header 1 x Power LED / Speaker Header 1 x RGB Header 1 x TPM (SPI_TPM) header 2 x USB 2.0 Header 1 x USB 3.2 Gen1 Header 1 x USB 3.2 Gen2x2

Internal I/O

Usb 2 0 Connectors
2
Usb 3 2 Gen 1 3 1 Gen 1 Connectors
1
Usb 3 2 Gen 2x2 Connectors
1
Number Of Sata Iii Connectors
4
Front Panel Audio Connector
Yes
Atx Power Connector 24 Pin
Yes
Cpu Fan Connector
Yes
Number Of Cpu Fan Connectors
2
Number Of Chassis Fan Connectors
4
Eps Power Connector 8 Pin
Yes
Number Of Eps Power Connectors 8 Pin
2
Tpm Connector
Yes
12v Power Connector
Yes
Number Of Water Pump Connectors
1
Rgb Led Pin Header
Yes
Number Of Rgb Led Pin Headers
4

Memory

Supported Memory Types
DDR5-SDRAM
Number Of Memory Slots
4
Memory Slots Type
DIMM
Memory Channels
Dual-channel
Ecc Ompatibility
ECC & Non-ECC
Maximum Internal Memory
256 GB
Unbuffered Memory
Yes

Network

Ethernet Lan
Yes
Ethernet Interface Type
2.5 Gigabit Ethernet
Lan Controller
Dragon RTL8125BG
Wi Fi
No

Packaging content

Cables Included
SATA
Screws Included
Yes

Processor

Processor Manufacturer
AMD
Socket
Socket AM5
Compatible Processor Series
AMD Ryzen 7000 Series, AMD Ryzen 8000 Series, AMD Ryzen 9000 Series
Supported Processor Sockets
Socket AM5

RAM Memory Support

Memory Type
DDR5
Memory Channel
Dual (2)
Memory Type Ecc
ECC/Non-ECC
Memory Type R U
UDIMM (Unbuffered)
Memory Speed Mhz
DDR5 - 8000(OC)
Max Memory Capacity
256GB

Rear panel I/O ports

Usb 2 0 Ports Quantity
6
Usb 3 2 Gen 1 3 1 Gen 1 Type A Ports Quantity
4
Usb 3 2 Gen 1 3 1 Gen 1 Type C Ports Quantity
1
Usb 3 2 Gen 2 3 1 Gen 2 Type C Ports Quantity
1
Ethernet Lan Rj 45 Ports
1
Hdmi Ports Quantity
1
Hdmi Version
2.1
Headphone Outputs
3
Line In
Yes
Microphone In
Yes
Usb Connector Type
USB Type-A, USB Type-C

Storage controllers

Supported Storage Drive Types
HDD & SSD
Supported Storage Drive Interfaces
PCI Express 3.0, PCI Express 4.0, PCI Express 5.0, SATA III
Number Of Storage Drives Supported
8
Raid Support
Yes
Raid Levels
0, 1, 10

Weight & dimensions

Width
305 mm
Depth
244 mm

General

Audio
7.1 Channel HD Audio