NetBSD supports eight "tier I" architectures: 32-bit and 64-bit x86 and Arm, plus MIPS, PowerPC, Sun UltraSPARC, and the Xen hypervisor. Alongside those, there are no less than 49 "tier II" supported architectures, which are not as complete and not everything works -- although almost all of them are on version 9.3 except for the version for original Acorn computers with 32-bit Arm CPUs, which is still only on NetBSD 8.1. There's also a "tier III" for ports which are on "life support" so there may be a risk Archimedes support could drop to that. This is an OS that can run on 680x0 hardware, DEC VAX minicomputers and workstations, and Sun 2, 3, and 32-bit SPARC boxes. In other words, it reaches back as far as some 1970s hardware. Let this govern your expectations. For instance, in VirtualBox, if you tell it you want to create a NetBSD guest, it disables SMP support.