Board Layout

The MSI MAG B660M Mortar WiFi DDR4 takes a modest approach to the design—no RGB lighting to speak of, and it is using an M-ATX form factor to allow for more compact computer builds. Flip it around and the back also has an alteration to the standard with the inclusion of warning zones showing possible conflicts with cases and where the standoff should be placed.


With either the Z690 or B660 chipset, this new LGA 1700 socket will need a new retention bracket for air-cooler and AIO if the mounting holes do not line up. The VRM heatsinks are not overly tall, but caution is advised for air-coolers that may extend outside the socket zone.


The MSI MAG B660M Mortar WiFi DDR4 offers two PCI Express x16 slots. The first slot is wired PCIe Gen4 with a total of x16 lanes coming from the CPU and reinforced for extra stress support. It is also backwards compatible, allowing older PCIe devices to work Gen3 without issues. The second slot is also physically x16, but internally wired for x4 PCIe Gen3, leaving a single x1 slot in between.


There are two M.2 sockets on the MSI MAG B660M Mortar WiFi DDR4, both of which are Gen4 x4, and all feature full-coverage heatsinks. The upper M.2 socket lane is provided by the CPU with the second socket's bandwidth coming from the PCH (B660). If populated, SATA port #8 will be disabled.


Even though this is an entry-level product, having debug LEDs is a useful tool when tracking down boot issues.


The board has a total of six SATA 6 Gb/s ports on the side, four of which are angled 90 degrees from the board. Two additional SATA ports are located at the bottom. Labeled as SATA A/B, these two are separated from the others, with data bandwidth provided by the ASM 1061 SATA controller instead.


The MSI MAG B660M Mortar WiFi DDR4 has a limited amount of high bandwidth USB ports, with a single 20 Gbps and three 10 Gbps ports. Besides those, the standard assortment is accounted for. These include the optical S/PDIF Out port, Wi-Fi 6, and 2.5 Gb LAN. Four additional USB 2.0 ports are available for peripherals, like a keyboard, mouse, USB headphones or game controller. All of these generally do not consume enough bandwidth to warrant the 10 Gbps ports on these devices.

• 1x DisplayPort
• 1x HDMI 2.1 port
• 3x USB 3.2 Gen 2 10 Gbps Type-A ports
• 1x USB 3.2 Gen 2x2 20 Gbps Type-C port
• 1x Intel 2.5G Ethernet
• 2x Wi-Fi antenna connectors
• 5x audio jacks
• Optical S/PDIF Out port