Age of Kings - Age of Conquerors :
HD Edition :
reduce your screen resolution to increase performance (not entirely, but to get optimal performance)
Tactics for recording : -if you are on Windows 10 : use Windows recorder Alt + G (best option in my opinion) but only for individual runs if you are on AoK and AoC because it stops abruptly when the window changes screen resolution (default 800x600 fastest resolution for speedruning)
-you can use OBS for streaming if you want but be carefull, if you play on HD Edition and if your pc is bad, this can ruin your runs and the time is not in game (x2) but RTA (reduce the bitrate of your stream or non-stream if the lag appears in the level)
-don't use Windows recorder if you switch version (HD to AoC...)
If you play individual campaign - full campaign / or a level requiered with dark age glitch, use SSD hard drive for reducing load time