Low Earth Orbit (LEO) which the ISS is in is very different from deep space. You can get away with much less radiation hardening in LEO. For example, I know a company consumer-grade Xilinx MPSoCs with 4xA53 cores at 1.5GHz.
They do modify them slightly to remove the lithium-ion batteries, which you do not want inside a space craft.
I think they replace them wit NiMH cells if the devices still need to be battery powered.