Introducing the MSI MAG B850M MORTAR WIFI: A Compact Powerhouse for AMD Ryzen 9000 Series
Today, we're excited to unbox and review one of MSI's latest offerings tailored for gamers and PC builders — the MSI MAG B850M MORTAR WIFI motherboard. Designed specifically for AMD Ryzen 9000 series processors, this motherboard combines robust performance, cutting-edge features, and a sleek, military-inspired design in a micro-ATX form factor.
Packaging & First Impressions
The box features MSI’s signature dark military aesthetic with a black-gray color scheme and sharp, angular graphics. On the front, the motherboard’s name is prominently displayed alongside the “AMD Ryzen 9000 Ready” label. Inside, the packaging includes a comprehensive set of accessories: Wi-Fi 7 antenna, SATA data cable, front I/O extension, multiple extension cables for RGB, M.2 screws, and tools for easy installation.
Design & Build Quality
The motherboard continues MSI’s tradition of dark, armored looks, with a matte black PCB and green accents. The large heatsinks covering VRMs and the chipset sport a textured finish, ensuring efficient cooling for high-performance workloads. 
Let's Look at the top half of the motherboard.
The center features the AMD Socket AM5, supporting AMD Ryzen 9000, 8000, and 7000 series desktop processors. The CPU cover is also black with a fluorescent green accent and features the MSI MAG logo. The motherboard is equipped with MSI's latest AI MSI Click BIOS X, featuring multiple one-click overclocking functions. It quickly and intelligently assesses the processor's overclocking potential and system cooling conditions, providing overclocking setting recommendations, enhancing computing power, accelerating AI processing, and fully realizing performance limits. The motherboard also features multiple thermal and overcurrent protections, as well as a grounding structure unique to MSI. This patented design suppresses electromagnetic interference (EMI) generated by the power phases and helps effectively conduct heat to the grounded copper planes.
The power supply area is covered with a large, integrated dark-style I/O and VRM heatsink on a black PCB, with fluorescent green accents adding a vibrant look. The MSI MAG B850M MORTAR WIFI motherboard features 12+2+1 Duet Rail digital power phases, dual power ports, and a 60A SPS intelligent power module to fully unleash the processor's optimal performance.
The side adopts a stacked design to provide a larger heat dissipation area and better heat dissipation efficiency.
The left side's main power supply and I/O heatsink is incredibly thick, featuring a fluorescent green MSI MAG logo at the top and MSI branding and a diagonal UV print underneath. This is only visible from certain angles, creating a very discreet look. MSI's oversized heatsink ensures optimal performance even under high loads.
The right side of the heatsink features a stacked design, providing a larger heat dissipation area and improved cooling efficiency. Underneath, a high-quality 7W/mK MOSFET thermal pad and an additional choke pad ensure high performance across all cores.
A thick VRM heatsink covers the upper MOS to help dissipate heat. A fluorescent green MAG logo is printed on top.
The multi-layer stacked extended design allows for a larger heat dissipation area and better performance. The bottom is also covered with a high-quality 7W/mK MOSFET heatsink and an additional choke heatsink to ensure low-temperature and stable operation of the power inductor.
The CPU power connectors are located on the top left of the motherboard, featuring dual 8-pin connectors. They provide ample power for overclocking multi-core processors. MSI motherboards feature a solid-pin design for their 4-pin, 8-pin, and 24-pin power connectors. This design offers the advantage of more secure and stable 12V power delivery to the processor when handling high current loads.
The MSI MAG B850M MORTAR WIFI motherboard features four DDR5 memory slots with a convenient single-sided clip-on design and advanced SMT soldering technology (Surface Mount Technology). This reduces solder joint defects, electromagnetic interference, and noise, ensuring a clean, high-speed DDR5 signal. It supports up to 256GB (4 x 64GB) and supports XMP 3.0 overclocking and AMD EXPO overclocking. It can overclock up to DDR5-8200MHz (OC+). MSI's signature "Memory Try It!" and "High-Efficiency" modes optimize memory performance by increasing memory bandwidth and reducing latency. To the right of the memory slots is the motherboard's 24-pin power connector. Above the power connector is the motherboard's debug indicator. At the top are the CPU fan, pump-sys fan, sys fan, and 5V 3-pin ARGB header. The gray connector is the multi-function fan port, serving as both a pump and a fan. It automatically detects whether it's a pump or a PWM/DC fan, and its distinctive gray design makes it easy to identify. All connectors are optimally positioned (including a dedicated water pump power connector) and can be connected to MSI radiators and chassis for seamless integration and synchronization.
A USB 3.2 Gen 2 10Gbps Type-C front port is provided below the power supply port.
Then, let's take a look at the bottom half of the motherboard.
Above the PCH chipset and each M.2 slot are thick black aluminum alloy heatsinks. The surface of the heatsink features a horizontal graining process to increase the heat dissipation area, providing excellent heat dissipation while maintaining a unified look.
First, let's look at the PCIe interface. The motherboard features two PCIe slots. The top two are LIGHTNING GEN 5 PCI-E x16 slots, boasting a bandwidth of up to 128 GB/s, double the speed of the previous generation. These PCI-E slots utilize advanced SMT soldering technology (Surface Mount Technology) to reduce interference and electrical noise, fully supporting the higher bandwidth and transfer speeds of PCI-E 5.0 signals. From top to bottom, they are: one PCIe 5.0 x 16 high-strength graphics card slot (x16), provided by the CPU; and one PCIe 4.0 x 4 slot (x4), provided by the chipset. The first PCIe slot features the latest second-generation Steel Armor for enhanced anti-interference capabilities and improved electrical performance. The most significant change to this generation of the B850M MORTAR WIFI Mortar is the repositioning of the PCIe slot and M.2 slot. MSI placed the PCIe 5.0×16 graphics card slot first, and the two M.2 slots on the front were placed below the graphics card slot. After raising the graphics card slot, in some compact chassis, the space from the slot to the bottom of the chassis will be greatly increased, which will help to accommodate thicker high-end graphics cards.
The first PCIe 5.0 x 16 graphics card slot supports quick-release graphics cards. A simple press of a button on the right side locks the graphics card slot open, eliminating the need to hold the button with one hand while removing the graphics card with the other, making it much more convenient for gamers. An icon next to the button changes with the lock's status, indicating the current lock status.
The motherboard's M.2 slots. The motherboard features two PCIe 5.0 M.2 SSD slots (front) and one PCIe 4.0 M.2 SSD slot (back). The two front M.2 slots utilize a second-generation magnetic, tool-free M.2 heatsink, with a fluorescent green "MORTAR" logo centered to the right.
The fluorescent green arrow on the left is the M.2 quick-release button. The H on the left side of the heatsink also has "01, 02" printed on it, indicating the SSD slot.
After removing the heat sink armor, you can see that a high-quality 7W/mK MOSFET cooling pad is pre-attached to the back of the heat sink armor.
The first M.2 SSD slot is displayed. You can see that a high-quality 7W/mK MOSFET thermal pad is also pre-attached to the bottom. The built-in double-sided M.2 thermal solution allows the M.2 SSD to run faster without slowing down, protecting data security. Looking at the parameters, the first one is: 1 x M.2 2280/2260 (PCIe 5.0 x4), provided by the CPU; the second one is: 1 x M.2 2280/2260 (PCIe 5.0 x4), provided by the CPU. The M.2 SSD installation adopts MSI's second-generation exclusive EZ M.2 CLIP design. After the M.2 SSD is inserted into the slot, gently push the latch to lock it to ensure that the SSD is installed in place. When removing it, you only need to flip the latch outward, and it can be easily removed with just one finger. Both slots are equipped with a fixing knob on the left end, which can be rotated to secure the tail of the M.2 SSD.
The chipset heatsink on the right side features an enlarged PCH heatsink and a fanless design to reduce dust and noise while maintaining optimal cooling efficiency. "MSI ARSENAL GAMING" is printed in fluorescent green above the chipset heatsink.
To the left of the motherboard's shielded cable is the onboard audio area, housing its own dedicated audio circuitry. It features a high-definition ALC4080 audio processor, premium audio capacitors, a headphone amplifier, DE-POP protection, and support for Audio Boost 5, delivering studio-grade sound quality for the most immersive gaming experience. The rear audio I/O connectors feature MSI's unique isolation design for crystal-clear audio. The metal frame completely isolates the audio port from the internal components, ensuring crisp, noise-free sound.
Let's take a look at the connectors on the bottom of the motherboard.
From left to right: 1 x front audio connector, 1 x 12V 4-pin RGB connector, 1 x 5V 3-pin ARGB connector, 1 x JDP1 connector, 1 x JDASH1 connector, 1 x Sys Fan connector, 1 x EZ Connect connector, 1 x 8-pin power connector, and 2 x USB 2.0 9-pin expansion connectors.
An 8-pin power connector on the lower right side of the motherboard provides auxiliary power to the graphics card, facilitating extreme overclocking. The exclusive PCIE power architecture design provides a more stable and secure dedicated power supply for high-end graphics cards, preparing for the future era of AI computing. An additional EZ Connect connector below, coupled with an adapter cable, expands fan, data, and ARGB lighting connections.
The EZ Conn interface, combined with the matching PWM+5V ARGB+USB 2.0 three-in-one adapter cable, allows for expansion of fan, ARGB lighting, and USB 2.0 data interfaces, while making installation easier in confined environments.
There are also abundant interfaces in the lower right corner, including 1 x front USB 3.2 Gen1 5Gbps interface, 1 x Front Panel, 1 x 5V3Pin ARGB, 2 x Sys Fan and other interfaces.
The front panel interface of the chassis is equipped with a dedicated extension cable, which can facilitate wiring in a small chassis like ITX, making it more user-friendly.
On the far left side of the bottom of the motherboard, there are 4 SATA6 interfaces on the left side for hard drive expansion, which are native to the chipset.
The back of the motherboard, it's a pure black PCB with excellent workmanship and plump solder joints. However, it lacks metal armor.
Full metal AM5 base backplate.
At the bottom of the motherboard's back is the M.2_3 slot, supporting up to PCIe 4.0 x2 and SATA, with a length of 2280 mm. This slot is provided for the chipset. Due to space limitations, the rear M.2 slot lacks heatsink protection. It's recommended to install a thin heatsink and thermal paste to aid cooling, depending on the motherboard stud clearance. The AM5 backplate also features the series certification icons
Looking at the rear I/O interfaces, they are very rich, from left to right: 1x BIOS FlashBack button, 1x Clear CMOS button, 1 x HDMI 2.1, 1x Realtek 8126-VB 5G LAN network card, 1 x USB 3.2 Gen2 TypeA 10Gbps (supports BIOS FlashBack), 2 x USB USB 3.2 Gen2 TypeA 10Gbps, 1 x USB USB 3.2 Gen2 TypeC 10Gbps, 4 x USB USB 3.2 Gen1 TypeA 5Gbps, 1 x USB USB 3.2 Gen2 TypeC 20Gbps, 2 x Wi-Fi 7 wireless quick-release terminals (supports Bluetooth 5.4), 1x optical S/PDIF output, and 2 x 3.5mm audio jacks.
Wi-Fi 7 shark fin antenna with the MSI logo engraved on it.
The Wi-Fi 7 wireless terminal adopts MSI's new easy-to-detach design, and all interfaces are gold-plated terminals.
The snap-on design allows you to lock it by simply inserting it, and it is also very convenient to remove.
Wi-Fi 7 antenna connection to the motherboard. The MSI MAG B850M MORTAR WIFI motherboard uses the latest Wi-Fi 7 wireless networking solution. The new 320MHz bandwidth increases the maximum bandwidth to 5.8Gbps, 2.4 times that of WiFi6/6E.
Next, we'll go through and disassemble the motherboard.
The back of the thick CPU power supply heat sink contacts the MOSFET and inductor through the thermal pad, and the contact surface pressure is good.
There is also a thermal pad on the back of the chipset heat dissipation module to fit the chipset heat dissipation.
The solid M.2 heatsink is lined with a high-quality 7W/mK MOSFET thermal pad.
The motherboard comes pre-installed with a black integrated I/O shield. This shield, combined with an additional layer of sponge and a rust-resistant stainless steel I/O cover, reduces static electricity and electromagnetic radiation noise from the system, and is more durable than traditional I/O covers.
The lower left corner is based on the Realtek ALC4080 Codec single-chip audio solution.
The center of the two M.2 slots is the Nuvoton NCT6687D-R chip that provides functions such as operating status monitoring.
The back of the motherboard. The right side of the all-metal AM5 base backplate also features an auxiliary power inductor.
What do you think of the MSI MAG B850M MORTAR WIFI? In our next article, we’ll be testing it with the following setup: CPU – AMD Ryzen 9 9900X, Motherboard – MSI MAG B850M MORTAR WIFI, Graphics Card – GALAX GeForce RTX 4080, RAM – Kingston Fury Renegade DDR5 RGB 6400 32GB (16GB x2), SSD – WD_BLACK SN8100 2TB, and Software – Aida64 V7.70.7500, CrystalDiskMark 8.0.6 x64. Stay tuned and share your thoughts in the comments!
