Specifically it’s the AsRock ab350 pro 4.
This should be the one. It appears they supported up to the 3950x. They don’t show the 5000 series as officially supported, but the latest beta bios added support for them. If you go to the page for bios it’s towards the bottom. The bios is now version 7.20.
It works pretty well, with the 5600x and that bios I was even able to enable smart access memory for my 6700xt.
https://www.asrock.com/mb/AMD/AB350 Pro4/#Overview
Specs
5600x-using a wraith prism cooler
AsRock ab350 pro 4
16gb ddr4 3000, though I’ll probably pull that and pick up 32gb ddr4 3200
240gb Samsung 960 evo
2 1tb sata ssd drives
MSI mech 2x 6700xt
Corsair rmx 850 watt
Cooler master case, I think it’s the mb511