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In terms of loading config files ( files that end with .cfg), Half-Life always looks for and loads configs in this order :

(1) 3dfx.cfg
Located in C:\Half-Life\valve\hw\ and not created when you installed the game.You need to create a such-named file if you have a Voodoo1/2 and chose OpenGL/3Dfx MiniGL as your video driver in-game.If you don't create a such-named .cfg,you'll see "couldn't exec 3dfx.cfg" in the console during game start-up(not a problem,the game's merely reporting it couldn't find the file).
(2) opengl.cfg
Located as above.This config is for video cards other than Voodoo1/2 and has an OpenGL ICD. Not created when you installed the game.Again,If you don't create a such-named .cfg,you'll see "couldn't exec opengl.cfg" in the console during game start-up(again,not a problem,the game's merely reporting
it couldn't find the file).
(3) joystick.cfg
Located in C:\Half-Life\valve\. Joystick configurations. Not created during install. Go to Mad Dog's site listed further on for explanation.
(4) autoexec.cfg
Located as above. Not created during install and is a user-created file. Some settings other than visual ones can be included within this file.

So, if you want my visual config settings to take effect automatically when you start the game (well,most of them anyway...some still require you start,quit and restart the game for it to take effect), you'll want to name the config as 3dfx.cfg and place it in the proper directory as outlined above and ensure no similarly-named cvar setting is listed in any other differently named .cfg file located in the /valve/ or /valve/hw/ folder.

If for some reason things get screwed up after using my config (it shouldn't unless you change values here and there and got confused), simply delete the config file from the game's folder (whichever folder/sub-folder you put it in), start the game and type "exec default.cfg" (without the quotes) at the console,quit the game and restart. Half-Life will then revert to its default configuration.This default.cfg is included in my zipped package for this very reason (see further on under "Some Notes").
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