MSI PRO B850M-A WiFi AM5 mATX Motherboard
- Processor Socket: Socket AM5
- Chipset Type: AMD B850
- Chipset Family: AMD
- RAM Memory Technology: DDR5
Last refreshed Sep 7, 2026 · Based on the Amazon listing and published specifications, not hands-on testing.
A well-equipped mid-range AM5 motherboard for a compact Ryzen build that wants modern connectivity without an X870 price tag.
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ASIN: B0FC97YJBRModel: B850M-ACategory: Motherboards
Overview
MSI PRO B850M-A WiFi mATX motherboard for AMD's AM5 socket, supporting Ryzen 9000, 8000 and 7000 series processors with DDR5 memory, PCIe 5.0, dual M.2 slots and Wi-Fi 7.
This is a mainstream B850 chipset board rather than a flagship X870, aimed at builders who want current-generation AM5 support and Wi-Fi 7 without paying for extra PCIe lanes or overclocking headroom they will not use. The 8-phase 60A VRM design and Frozr cooling are aimed at running a mid to upper Ryzen chip reliably rather than pushing extreme overclocks. Its mATX form factor fits smaller cases than a full ATX board while still offering dual M.2 storage.
- AM5 socket motherboard for Ryzen 9000/8000/7000 processors
- DDR5 memory support up to 8200+ MT/s overclocked
- PCIe 5.0 x16 slot plus M.2 Gen5 and Gen4 storage
- Wi-Fi 7 and 5Gbps LAN built in
Who it's for
Suits a builder assembling a new AM5 system with a current Ryzen 9000, 8000 or 7000 series CPU who wants DDR5, PCIe 5.0 storage and built-in Wi-Fi 7 in a compact mATX size. Not for someone who specifically needs the extra PCIe lane count or memory overclocking ceiling of a higher-tier X870 board.
Pros and cons
- Supports Ryzen 9000, 8000 and 7000 series on one AM5 socket
- Dual M.2 slots include a full PCIe 5.0 Gen5 connector
- Built-in Wi-Fi 7 and 5Gbps LAN
- MATX size limits total expansion slots versus a full ATX board
- No details given on total USB port count from the listing
Performance notes
The 8-phase 60A SPS VRM is built to run Ryzen 9000 series chips at their rated power targets, and the extended heatsink with MOSFET thermal pads is there to keep that VRM cool under sustained load rather than short bursts. The primary M.2 Gen5 slot runs at 128 Gbps for a current PCIe 5.0 SSD, while the secondary Gen4 slot at 64 Gbps suits a bulk storage drive, and EZ M.2 Shield Frozr II adds a heatsink to prevent throttling on the primary slot specifically. Wi-Fi 7 and 5Gbps LAN cover both wireless and wired networking without an add-in card.
Specifications
| Brand | MSI |
|---|---|
| Model | B850M-A |
| Dimensions & fit | |
| Ram Memory Maximum Size | 256 GBhigher than 59% of 23 motherboards |
| Item Weight | 2.9 pounds |
| Item Dimensions L x W x H | 11.2 × 11 × 2.9 inches |
| Capacity & performance | |
| Memory Storage Capacity | 256 GB |
| Power & efficiency | |
| Main Power Connector Type | 4+4-pin |
| Compatibility & installation | |
| Graphics Card Interface | PCI Express |
| Compatible Devices | Personal Computer |
| Warranty & support | |
| Warranty Description | 3 years |
| Other details | |
| Processor Socket | Socket AM5 |
| Chipset Type | AMD B850 |
| Chipset Family | AMD |
| RAM Memory Technology | DDR5 |
| CPU Model | Ryzen 9 |
| Memory Slots Available | 4 |
| Total PCIe Ports | 3 |
| Total Usb Ports | 8 |
| Total SATA Ports | 4 |
| Number of Ethernet Ports | 1 |
| Platform | Windows 11 |
| Number of Items | 1 |
| Number of Ports | 10 |
| Total Number of HDMI Ports | 1 |
| Mfr Part Number | PROB850MAWIFI |
Closest rivals on specs
ASUS TUF Gaming B850M-PLUS WiFi AM5 Motherboard- Item Weight 2.9 vs 2.6 pounds (+12%)
- Memory Storage Capacity 256 vs 192 GB (+33%)
- Ram Memory Maximum Size 256 vs 192 GB (+33%)
Frequently asked questions
Which Ryzen processors work with the MSI PRO B850M-A WiFi?
It supports AMD Ryzen 9000, 8000 and 7000 series processors on the AM5 socket.
How many M.2 slots does this board have?
Two, a PCIe Gen5 x4 slot rated at 128 Gbps and a PCIe Gen4 x4 slot rated at 64 Gbps.
Does this board include Wi-Fi?
Yes, it has a built-in Wi-Fi 7 module with Bluetooth 5.4, alongside a 5Gbps wired LAN port.