Pretty much, although I think the RTG is mounted on a limb as far away from the other equipment as possible, but still the computer needs to be able to tolerate a decent amount of radiation. It also has an interesting redundant design where it has double the component count and can either exploit that for extra compute or redundancy in case of component failure.
Solar particles become less of a threat, but the sun's atmosphere actually shields the solar system from some types of cosmic rays. Don't know what proportion of electronics faults stem from each, though.
