Could be anything. If you have nvidia I recommend the new nvidia app (beta) instead of shadowplay (being replaced by nvidia app) for clips etc. Otherwise remove as much clutter from your pc as possible, make sure it’s physically clean, good working temps/airflow, set the game to play on performance mode, try not to have other software running unnecessarily like chrome tabs etc, and also make sure the game is installed on m.2/nvme ssd if you have it, or just your fastest drive.