MAG B860M MORTAR WIFI Motherboard Guide: Specs, Features, and Compatibility

The MSI MAG B860M MORTAR WIFI is a Micro-ATX motherboard built on the B860 chipset, designed for use with Intel processors using the LGA 1851 socket. This motherboard supports Intel Core Ultra 200 Series processors.

Key features include support for up to 256 GB of memory, up to PCIe 5.0, 2 PCIe slots, 3 M.2 slots, 5Gb Ethernet, and Wi-Fi 7.

MAG B860M MORTAR WIFI Specifications

Chipset	B860 — Learn more about LGA 1851 socket chipsets
CPU Support	Intel Core Ultra 200 Series (LGA 1851 socket)
Memory	256 GB max DDR5, up to 9200 MT/s, Dual Channel, 4 DIMM slots
Storage	3 M.2 slots (PCIe 5.0 x4, PCIe 4.0 x4, PCIe 4.0 x4), 4 SATA ports
PCIe Slots	2 PCIe slots (PCIe 5.0 x16, PCIe 4.0 x4)
Ethernet	5Gb
Wi-Fi	Wi-Fi 7
Bluetooth	5.4
USB Ports	9 rear panel, 7 via internal headers (up to USB 10Gbps)
Audio	Realtek ALC897
Form Factor	Micro-ATX

The MAG B860M MORTAR WIFI uses an LGA 1851 socket for Intel processors. A motherboard's chipset and socket type determine CPU compatibility and cannot be changed.

The MAG B860M MORTAR WIFI is compatible with the following processors:

• Intel Core Ultra 200 Series

A motherboard's chipset and socket type determine which CPUs it can support. If you plan to upgrade your CPU later, verify that the motherboard supports newer processors in the same socket family.

The importance of CPU upgradeability depends on your use case:

• High-end builds: Purchasing a high-end CPU from the start means you likely won't need to upgrade for 5-7 years. Future CPU support is less critical.
• Mid-range builds: Starting with a mid-range CPU with plans to upgrade in 2-3 years makes CPU compatibility important. However, by upgrade time, new socket types may offer better value.

Most users keep their CPU until they replace the entire system. The motherboard's chipset features, connectivity, and current-gen CPU support often matter more than future CPU compatibility. Instead of buying a budget CPU with plans to upgrade, consider saving up for the CPU you want; the performance difference between budget and mid-range CPUs is significant.

The MAG B860M MORTAR WIFI supports up to 256 GB of DDR5 memory across 4 DIMM slots (RAM slots) in Dual Channel configuration. For best performance, install memory in matching pairs (identical speed, capacity, and timings) to enable dual-channel mode.

With a maximum capacity of 256 GB of RAM, the MAG B860M MORTAR WIFI is well-suited for memory-intensive workloads like content creation, video editing, 3D rendering, and virtualization. Most gaming and general-purpose users will find 32-64 GB more than sufficient.

A dual-channel memory configuration doubles memory bandwidth compared to single-channel. Install memory in matching pairs (2x or 4x modules of the same specification) to enable dual-channel mode. This significantly improves performance in gaming, content creation, and general system responsiveness.

• Memory Type: DDR5
• Maximum Capacity: 256 GB
• DIMM Slots: 4
• Channel Configuration: Dual Channel

The MAG B860M MORTAR WIFI supports memory speeds up to 9200 MT/s (overclocked).

High-Performance Memory: 9200 MT/s is excellent for high-end gaming and professional applications. Faster memory provides better frame rates in CPU-bound gaming scenarios. It also improves performance in memory-intensive workloads. However, the real-world performance gains diminish beyond 6000 MT/s for most users.

For most users, having more RAM is more important than having faster RAM. Faster RAM provides measurable benefits in gaming and content creation, but the gains diminish at higher speeds.

RAM Speed Recommendations

RAM Speed	Gaming Performance	Productivity/Office	Content Creation
5200-5600 MT/s DDR5	Good: Solid performance for gaming	Excellent: Speed doesn't matter for office tasks	Good: Adequate for most workflows
6000 MT/s DDR5	Excellent: Noticeable improvement in CPU-bound games. Sweet spot for modern platforms.	Excellent: Speed doesn't matter for office tasks	Excellent: Noticeable improvement in rendering, compression, and video encoding
7000+ MT/s DDR5	Diminishing returns: Minimal gains over 6000 MT/s at significantly higher cost	Excellent: Speed doesn't matter for office tasks	Diminishing returns: Marginal improvement over 6000 MT/s, not worth the premium

The MAG B860M MORTAR WIFI supports the following memory overclocking profiles: XMP.

Memory Overclocking Explained: These profiles allow your RAM to run at its advertised speed (which is technically an overclock beyond standard JEDEC specifications). Simply enable the appropriate profile in your BIOS to unlock your memory's full performance. Without enabling these profiles, your high-speed RAM will run at much slower standard speeds. You can also manually overclock memory if you prefer fine-tuned control.

Choose your memory capacity based on your specific use case:

How Much RAM Do You Need?

RAM Amount	Use Cases
16 GB	Gaming: Bare minimum for basic gaming Development: Web development, basic coding, office work
32 GB	Gaming: Sweet spot for gaming in 2025; handles any game, browser tabs, Discord, and background apps without issues Content Creation: Entry point for video editing, photo editing, and light 3D work Development: Running Docker containers, virtual machines, Android Studio, large IDEs
64 GB	Gaming: Only beneficial if you stream, record, or run heavy background applications Content Creation: Ideal for 4K+ video editing, large Photoshop projects, After Effects, and moderate 3D rendering Development: Multiple VMs simultaneously, large database work, extensive containerized development
128 GB+	Content Creation: Professional workflows with 8K footage, complex 3D scenes, simulation work, or multiple virtual machines Development: Extensive virtualization and enterprise-scale development

The MAG B860M MORTAR WIFI provides 3 M.2 NVMe slots for high-speed SSDs and 4 SATA 6 Gb/s ports for 2.5" SSDs and hard drives. The 4 SATA ports provide adequate connectivity for additional storage drives beyond your primary M.2 SSDs. SATA is ideal for mechanical hard drives used for mass storage or backup purposes.

M.2 NVMe Slots on the MAG B860M MORTAR WIFI

M.2 Slot	Interface	Theoretical Bandwidth	Connection	Form Factors
#1	PCIe 5.0 x4	16 GB/s	CPU	2242, 2260, 2280
#2	PCIe 4.0 x4	8 GB/s	Chipset	2260, 2280
#3	PCIe 4.0 x4	8 GB/s	Chipset	2260, 2280

M.2 NVMe SSDs are significantly faster than SATA drives and install without cables. The PCIe generation and lane count determine maximum transfer speeds. Actual speeds depend on both the slot and the drive; a PCIe 3.0 drive in a PCIe 5.0 slot runs at PCIe 3.0 speeds. PCIe is backward compatible: a PCIe 4.0 drive works in a PCIe 3.0 slot at PCIe 3.0 speeds.

M.2 Performance

Interface	Theoretical Bandwidth	Performance
PCIe 5.0 x4	16 GB/s	Cutting-edge, future-proof
PCIe 4.0 x4	8 GB/s	Excellent for gaming and professional work
PCIe 3.0 x4	4 GB/s	Still very fast, suitable for most users
PCIe 3.0 x2	2 GB/s	Slower, avoid for primary drives

For gaming, faster SSDs primarily improve load times rather than in-game performance. The exception is large open-world games that stream content as you play. PCIe 4.0 already provides fast load times, and while PCIe 5.0 can reduce load times further, the real-world difference is often negligible for most games.

How Many M.2 Slots Do You Need?

Slot Count	Assessment	Configuration
1 M.2 slot	Minimum viable	Works if you only need one NVMe and will use SATA for additional storage
2 M.2 slots	Ideal for most users	One NVMe boot drive + one games/storage drive
3+ M.2 slots	Enthusiast/professional	Useful for separating OS, games, and work files

Supported RAID Levels: 0, 1, 5, 10

The MAG B860M MORTAR WIFI offers 2 PCIe expansion slots for graphics cards, network adapters, sound cards, or other expansion devices.

PCIe Slots on the MAG B860M MORTAR WIFI

Slot	Physical Size	Specification	Theoretical Bandwidth	Lane Source
Slot 1	x16	PCIe 5.0 x16	64 GB/s	CPU
Slot 2	x4	PCIe 4.0 x4	8 GB/s	Chipset

The PCIe generation and lane count determine bandwidth for expansion cards. Higher bandwidth enables better performance for graphics cards, storage controllers, and network adapters. A slot's physical size (x16, x4, x1) doesn't always match its electrical lanes; a physically x16 slot might only provide x4 electrical lanes. Check the "Specification" column in the table above for actual lane counts.

PCIe Bandwidth

PCIe Configuration	Theoretical Bandwidth	Ideal Use Cases
PCIe 5.0 x16	64 GB/s	Latest generation GPUs, future-proof for next-gen graphics cards and high-bandwidth accelerators
PCIe 4.0 x16	32 GB/s	Current high-end GPUs, professional graphics cards
PCIe 3.0 x16	16 GB/s	Mid-range and older GPUs, most graphics cards won't saturate this bandwidth
PCIe 4.0 x4	8 GB/s	High-speed NVMe SSDs, sound cards, 10GbE network adapters
PCIe 3.0 x4	4 GB/s	Standard NVMe SSDs, sound cards, network adapters
PCIe 3.0 x1	1 GB/s	Basic expansion cards (USB controllers, low-speed network adapters)

PCIe 4.0 x16 is fully adequate for all current graphics cards. PCIe 5.0 GPU support provides minimal real-world benefits as no current GPUs saturate PCIe 4.0 bandwidth. PCIe 3.0 x16 works well for mid-range GPUs but can cause noticeable performance loss on high-end cards. All PCIe generations are backward compatible, so newer GPUs will work in older slots and vice versa.

Planning Your PCIe Expansion Slots

Build Type	Recommendations
Gaming	1x PCIe x16 slot for GPU. Most gaming motherboards include Wi-Fi and Bluetooth onboard, so typically only the GPU slot gets used.
Content Creation	1-2x PCIe x16 slots for GPU(s). Multi-GPU is obsolete for gaming but useful for rendering. May also need 1x PCIe x4 slot for sound card, 10GbE network card, or additional M.2 slots via adapter cards.
Workstation	Multiple GPUs for compute, professional sound cards, RAID controllers, or high-speed networking cards. Count your devices carefully as workstation builds use multiple slots.

The MAG B860M MORTAR WIFI includes 5Gb Ethernet for wired networking.

• 5Gb Ethernet (Intel Killer E5000)

Gigabit Ethernet (1 Gbps) handles most home internet connections and gaming. 2.5 Gigabit or faster Ethernet benefits multi-gigabit internet plans and large file transfers to network storage.

The MAG B860M MORTAR WIFI includes Wi-Fi 7 wireless connectivity. Built-in Wi-Fi allows PC placement without running Ethernet cables. Wired Ethernet offers more consistent performance for competitive gaming, but modern Wi-Fi 6E/7 works well for most users. If your motherboard lacks Wi-Fi, you can add a PCIe Wi-Fi card later.

• Chipset: Intel Killer BE1750x
• Frequency Bands: 2.4GHz, 5GHz, 6GHz
• 320MHz Channel Support: Yes (Wi-Fi 7 exclusive)
• Multi-Link Operation (MLO): Yes (Wi-Fi 7 feature for enhanced reliability)

Wi-Fi Speed Comparison

Wi-Fi Version	Benefits
Wi-Fi 7 (802.11be)	Latest standard with 320 MHz channels, 4K-QAM, Multi-Link Operation (MLO). Backward compatible with older devices; Wi-Fi 7 client devices needed for full performance. Ideal for 8K streaming, VR/AR, and ultra-low latency applications.
Wi-Fi 6E (802.11ax)	Adds 6 GHz band support for less congestion and interference. Excellent for gaming, 4K streaming, and high-bandwidth applications. Best choice for current high-performance builds.
Wi-Fi 6 (802.11ax)	Improved efficiency in crowded environments, better battery life for devices, lower latency. Current mainstream standard, great for most users.
Wi-Fi 5 (802.11ac)	Previous generation, 5 GHz only. Still capable for basic needs but lacks efficiency improvements of Wi-Fi 6/6E/7.

The MAG B860M MORTAR WIFI includes Bluetooth 5.4 for wireless keyboards, mice, headphones, and game controllers without USB dongles. Modern Bluetooth versions provide improved audio quality, range, and power efficiency.

The MAG B860M MORTAR WIFI provides 9 rear panel USB ports with the following connector types, plus internal headers for front-panel connections.

Rear Panel USB Ports on the MAG B860M MORTAR WIFI

Count	Standard	Speed	Connector	Features
3x	USB 2.0	480 Mbps	Type-A
1x	USB 2.0	480 Mbps	Type-A
3x	USB 10Gbps	10 Gbps	Type-A
1x	USB 10Gbps	10 Gbps	Type-C
1x	USB 40Gbps	40 Gbps	Type-C	Thunderbolt 4, DisplayPort Alt Mode

Internal USB headers are connectors on the motherboard that allow you to connect front-panel USB ports on your case, USB hubs, or other internal devices.

Internal USB Headers on the MAG B860M MORTAR WIFI

Header Count	Ports per Header	Standard	Speed	Header Type
1x	1x	USB 10Gbps	10 Gbps	Type-C
1x	2x	USB 5Gbps	5 Gbps	19-pin
2x	2x	USB 2.0	480 Mbps	9-pin

USB Speed Standards

USB Standard	Max Speed	Best Use Cases
USB4 40Gbps / Thunderbolt 3/4	40 Gbps	High-end docking stations, external GPUs, ultra-fast NVMe SSDs, professional video capture, multi-display setups
USB 3.2 Gen 2x2 / USB4 20Gbps	20 Gbps	High-speed external NVMe SSDs, 4K/8K video capture, fast file transfers
USB 3.2 Gen 2	10 Gbps	External SSDs, fast flash drives, high-resolution webcams, VR headsets
USB 3.2 Gen 1	5 Gbps	External hard drives, standard flash drives, hubs, general peripherals
USB 2.0	480 Mbps	Keyboards, mice, printers, older devices. Perfectly adequate for low-bandwidth peripherals.

Motherboard video outputs require a CPU with integrated graphics. The MAG B860M MORTAR WIFI provides the following display outputs:

• 1x HDMI 2.1 (up to 8K@60Hz)
• 1x DisplayPort 1.4 (up to 4K@60Hz)
• 1x USB-C with Thunderbolt 4 (DisplayPort 2.1) up to 8K@60Hz

Motherboards with video outputs enable troubleshooting even if you plan to use a dedicated GPU. If you're deciding between two similar motherboards and have a CPU with integrated graphics, prefer the one with video outputs; they add minimal cost.

The MAG B860M MORTAR WIFI features a Realtek ALC897 audio codec. Modern motherboard audio is sufficient for most users, including gaming and music listening. Consider a dedicated sound card or external DAC/amp for high-impedance headphones (250+ ohms), virtual surround sound processing for competitive gaming, or professional audio work requiring hardware DSP and ultra-low latency recording. For audiophile setups, external DAC/amps often provide better isolation from electrical interference than internal sound cards.

• Codec: Realtek ALC897

The MAG B860M MORTAR WIFI provides 5 total fan headers (1 CPU, 4 chassis).

• CPU Fan Headers: 1
• Chassis Fan Headers: 4
• AIO Pump Header: Yes
• 12V RGB Headers: 1
• 5V Addressable RGB Headers: 3

A CPU cooler compatible with the LGA 1851 socket will be required. Fortunately, existing CPU coolers designed for LGA 1700 remain compatible with LGA 1851, thanks to the identical mounting hole configuration.

• CORSAIR Nautilus 360 RS ARGB

  Supports LGA 1851:	YES
  Max TDP:	260 watt
  Type:	Liquid Cooler

• Check the latest price of the CORSAIR Nautilus 360 RS ARGB on Amazon

• Designed for Intel LGA 1851, 1700 and AMD AM5, AM4 sockets

• Three RS120 ARGB fans with Magnetic Dome bearings (544.6 gal/min airflow, 4.15mmH2O static pressure @ 1700 RPM)

• Direct 4-pin PWM motherboard connection with daisy-chaining support

• We estimate that this supports roughly a 260-watt TDP (Thermal Design Power).

• Ultra-quiet 20 dBA pump noise with Zero RPM fan mode

• 360mm aluminum radiator with 450mm flexible tubing

• Copper cold plate with pre-applied thermal compound

• Addressable RGB lighting on pump and fans (motherboard sync)

• Includes universal mounting hardware and 5-year warranty

• Noctua NH-D15

  Supports LGA 1851:	YES
  Max TDP:	220 watt
  Type:	Heatsink & Fans

• I found the dual 140 mm fans to be incredibly powerful, providing an impressive 220-watt TDP (183 NSPR) of cooling capability.

• With support for such a diverse range of CPU sockets, I found the Noctua NH-D15 to be a very flexible and adaptable cooling solution. Its supported socket types include Intel LGA 1851, 1700, 1200, 1156, 1155, 1151, 1150, 2011, 2066 and AMD AM4, AM3, AM3+, AM2, AM2+, FM2, FM2+.

• In my experience, the Noctua NH-D15 operates very quietly, with a noise level of just 24.6 dBA.

• I am extremely satisfied with the Noctua NH-D15 cooler and would highly recommend it to anyone who is looking for a high-performance and versatile cooling solution.

• Thermaltake TOUGHAIR 510

  Supports LGA 1851:	YES
  Max TDP:	180 watt
  Type:	Heatsink & Fans

• As someone who isn't a big fan of flashy LED lights, I appreciated the simplicity of the Thermaltake TOUGHAIR 510, which doesn't have any fancy lights but still looks great in my system.

• I found that the dual 120 mm fans on the TOUGHAIR 510 did an excellent job of keeping an LGA 1851 CPU cool, even under heavy workloads.

• If you're worried about the TOUGHAIR 510 taking up too much space in your system, Thermaltake offers a few single-fan variants that use different orientations, so you can choose the one that works best for your setup.

• With a max speed of 2000 RPM, the TOUGHAIR 510 provides optimal cooling performance when you need it most.

• With a 180-watt TDP (Thermal Design Power), the TOUGHAIR 510 offers solid cooling performance and is a great choice for anyone looking for a reliable and efficient cooling solution for their CPU.

The MAG B860M MORTAR WIFI uses the Micro-ATX form factor.

• Size: Micro-ATX (244mm × 244mm / 9.6" × 9.6")
• Case Compatibility: Fits Micro-ATX, mid-tower, and full-tower cases
• Expansion: Moderate expansion (typically 4 slots)
• Best For: Compact builds that still need some expansion capability

Micro-ATX is smaller than ATX but provides room for a graphics card and several expansion cards.

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