There is a rather cheap mainboard ASUS K14PA-U12 for 9004 EPYCs [1]. Strange, but it is missing support for 9005 Turin. How can this be (except of 400W+ models)? What do you think, could there be some true hardware issue making it impossible to workaround it in BIOS and thus no chance for coreboot either?

[1] https://servers.asus.com/products/servers/server-motherboard...

One thing that’s interesting with servers built with these cpus is that any M.2 drives tend to use the PCIe Gen 3 lanes. If there are two drives, one is likely x4 with the other x2. If you want fast boot drives it is important to pay attention to this.

As the Gigabyte MZ33-AR1 porting effort progresses, coreboot has to add definitions for I/O bus initialization, such as SATA, USB, and PCI Express. If you are curious how it is done on an AMD Turin-based system or want to educate yourself about modern server SATA, USB, and PCIe buses, this blog post is for you.