Board Layout

The MSI MAG B850 Tomahawk Max Wi-Fi has a very similar design to the Z890 and X870 models with most black theme with bright green details. There's no onboard RGB lighting and the M.2 heatsinks seem to be relatively small, especially given the top and mid heatsinks have PCIe Gen 5 capable slots underneath them. The rear of the PCB is relatively basic with no added heatsinks or backplates, but neither did the much more expensive MPG X870E Carbon Wi-Fi. Still, it's certainly more attractive than the very cheapest options on Socket AM5.


Being B850 there's just one chipset to contend with compared to two on X870X and that means there's more space on the PCB. It's good to see a push-button release here for graphics cards in the form of EZ PCIe Release, and we get a good view of the usually hidden mechanics of it from the button to the actual slot. Another MSI EZ feature is the EZ Conn connector. This combines a 4-pin fan header, 3-pin RGB header and USB 2.0 header into a single header, splitting them out into three cables and reducing cable clutter. It's simple to use and the fan header, for example, is separately labelled in the EFI. Very useful for dealing with the spaghetti from AIO liquid coolers, albeit still with the need for a fan splitter cable if you need to power more than one fan.


The EZ PCIe Release is a useful feature and necessary given the large M.2 heatsinks that surround the top M.2 slot these days, and it's no exception here. You'd really struggle to get your finger down to the slot release lever and having a push-button release just makes things easier and less haphazard. MSI's mechanism is push to open and push to close, so you need to press it again after removing your graphics card so it locks into place the next time. That adds a level of complexity that some might miss if they don't read the instructions, and while the ASUS method is certainly worse, Gigabyte's simply has a release button, with the latch closing as normal when you insert your graphics card.


MSI has sensibly offered a decent array of fan headers in the top right corner of the PCB so whether you have a 360 mm AIO liquid cooler and pump to power or large multi-fan air cooler, there are plenty of ports here, which can't be said for some of Gigabyte's options. The pump header you can see has a 3 A/36 W output and the CPU fan header offers 2 A/24 W, which is about as good as it gets and impressive for a sub $250 board. Moving down the right side of the PCB we have a USB 3.2 Gen 2x2 20 Gbps Type-C front panel header, which is the fastest USB port on the board and MSI hasn't dropped to two SATA ports here either as you get four which along with the USB 3.0 header, are all right-angled for easier cable tidying.


The M.2 ports comprise a pair of PCIe Gen 5 ports, plus two PCIe Gen 4 M.2 ports below them. Impressively the only lane sharing here is between the PCIe Gen 4 x16 slot and third M.2 port, with the former dropping from x4 to x2 if you use an SSD in that M.2 port. However, seeing as that M.2 port is limited to x2 rather x4, you probably don't want to be using it anyway. Starting at the bottom, the PCIe Gen 4 x4 M.2 port has its own small heatsinks and this only cools the top of the SSD. The port features a tool-free clip, but you'll need to grab a small screwdriver for the heatsink.


Moving up to the middle slots, these operate at PCIe Gen 5 x4 and PCIe Gen 4 x2 respectively, so if you have a PCIe Gen 4 SSD that tops out at 7,000 MB/sec, you'll probably want to avoid the PCIe Gen 4 x2 slot. Again both slots lack under SSD cooling, both have tool-free securing clips, but the larger heatsink again lacks a tool-free installation plus being blocked by your graphics card.


The primary PCIe Gen 5 M.2 port at the top finally has a tool-free heatsink, although it's not particularly large and even here there's no underside cooling for your SSD. This isn't so much an issue with PCIe Gen 4 SSDs but PCIe Gen 5 SSDs definitely run cooler cooled on both sides.


The I/O panel is a little spartan for liking with just seven Type-A USB ports and four of these are limited to USB 2.0 speeds. There's no USB4 here either, with the three Type-C ports limited to 10 Gbps a piece. Still, as we said at the start, if you just want to connect your gaming peripherals and would rather keep things to the essentials, we doubt you'd fine the I/O panel falling short. The only display output is an HDMI port, but you do get 5 Gbps Ethernet, Wi-Fi 7 and both a CMOS Clear button and USB BIOS Flashback button.