Abandonware Strategy games
Strategy games emphasis on managing complex situation. Reflexion is heavy and the choices are very vast. The video strategy games are usually quite different from chess, but the core gameplay is the same. You will find here lot of war games but also management games. Some of them are turn based whereas the other are real time and asks for a lot of quick thinking and good decisions.
In the Strategy genre, you may want to play 'Nam 1965-1975, 15 Move Hole Puzzle, 15 Piętnastka, 15 x 15, 1815. Those are just suggestions, you are welcome to download any game!