Put autoexec.cfg in ...\Steam\steamapps\common\Counter-Strike Global Offensive\csgo\cfg
or take what you want from it and add to your autoexec config!
After the Wild West Simulator 2015 update, video.txt needs to be put in ...\Steam\userdata\<Steam3 ID>\730\local\cfg
-novid -freq 144 -refresh 144 -tickrate 128 -maxplayers_override 50 -nojoy -nod3d9ex1 +exec autoexec.cfg