Fast update to this system that has been continually upgraded since 2017 - I took the plunge and got a 4K monitor, since prices were coming down. But I kept the old 1200p monitor, and found out that mixing DPIs on Linux with X11 is... interesting. I ended up using some
xrandr commands to get everything looking good, but after that, it's more than presentable. I hear Wayland will improve things.
Memory is overclocked to 2800 MT/s.
Moving from Ubuntu to Manjaro
I chose Ubuntu originally because I figured it would give me the best shot of running the RX 5700 XT on Linux without hassle. I was very wrong - getting everything to work nicely became painful, very quickly. So I moved back to Manjaro and set myself up on the unstable branch, in order to get the latest kernel and drivers. Cutting-edge software is where I really belong, after all. It's made a world of difference - everything Just Works now, and the stuff that wasn't running on Ubuntu (like Sekiro) does work here. Lesson learned, I definitely recommend picking one of the more up-to-date distros for new hardware.