Iso covers only x64, there’s no x86 architecture support for the ISO, AFAIK.
Issue seems related about access to RTC. And with some grub options, could be bypassed.
However, seems a kernel-related issue, so… maybe cannot be solved without an updated kernel.
which model/series of Ryzen 7? It could be an incompatibility with the CPU and CentOS 7.9.
Disabling some features (for instance, adding mce=off to the kernel boot options) or a more recent kernel could be needed (ELRepo’s kernel-ml…)
A better option could be to use some virtualitzation platform like proxmox instead of a bare-metal install. Here in the forum there is other people that can guide you better about it.
After some further investigation I think this is definately a kernel problem and I don’t see a way to resolve it with this version of Nethserver and 8.0 isn’t production ready yet so I’ll have to rey something else.