You need to disable IOMMU in the BIOS to install Windows Server 2016. You can enable it again after updating.Just purchased one. Using an epyc 7351p. Cannot install Windows server 2016 for some reason. Will install windows 10 without issues Will keep you updated as I figure out the problem, but currently not working well
You can find it under "AMD CBS -> NBIO Common Options -> NB Configuration -> IOMMU" in the BIOS.I saw that in other threads, but there is no option in the bios to do so on this board, at least I can't find the option.