Some things which I assume you already know [right? :)]

  • try the speed test, and by speedtest I mean the dslreports speed test, not the speedtest.net one;
  • turn off mouse smoothing and acceleration;
  • play on lan instead of wifi, if possible;
  • ultra settings don’t equal good system performance for 95 % of us. Try playing at modest[er] settings;
  • forward ports
  • overclock responsibly [!] gpu’s are expensive, here at least;
  • more FPS on monitor (refresh rate + fps output from gpu) = better experience.
  • kb+mouse trumps controller. Just because of the nature of approximation required while using either.
  • keep your pc clean.

*TBC