Get a high refresh rate (<1ms latency) LCD/LED monitor. This is by far the most important. It took a while to catch up to CRT latency, and it's still sold as a

Get a high refresh rate (<1ms latency) LCD/LED monitor. This is by far the most important. It took a while to catch up to CRT latency, and it's still sold as a niche product, but we are there. If you are in Linux, you may want to turn off your display compositor (KDE/XFCE), or use a lightweight xorg window manager like fluxbox or i3. This isn't necessary when using a fast GPU, but even then you may dislike animations. Use a text editor with a real GUI toolkit (not electron or similar) like emacs or gvim/nvim-qt. Unfortunately, emacs can struggle rendering syntax highlighting, but outside that it is lean and snappy. Hopefully the recent progress with tree-sitter will resolve that. I have met very few people who care about latency the way I do. I think most of it comes from my nostalgia of DOS-era computing. The most satisfying hardware purchase I have ever made is a good looking 2K IPS/VA 120hz/144hz+ freesync display. Millions of hours of my life experience were noticeably improved.