This surprises me as I have been using Linux Mint Cinnamon (currently on 18.2) for years now with no GPU rendering issues at all for both Cycles and Octane. And no issue running Blender from version 2.42, there is nothing in Cinnamon that should cause any issues. Like you surmised, it’s far more likely that running the 32bit version is what was causing your problems. The last time I ran a 32bit version of a Linux distro was about 12 years ago or more.
You’re right. I too don’t think that the edition was causing a problem. But since my rig is quite old, I used Xfce instead as some people reported it to be more stable and faster
