I’ve got the same board with 4x Micron/Crucial mtc20c2085s1ec48br DIMMs and while set to auto detect, the RAM only works at 3600MT/s. However if set manually to 4400MT/s in the BIOS it works fine, and has done for months. Technically out of spec per the datasheet/manual, but eh.
FWIW I also had some weirdness with video output on the board - out the box it defaults to the onboard IPMI/ASPEED (VGA) controller, rather than the iGPU on the CPU (DP and HDMI), which makes sense I guess, but would be nice if they made it a bit clearer.