sorta.....
Some of the 3d games (not fighters, mostly games like rush and blitz) used real 3dfx voodoo chips. Because of this, the video output is similar to a video card in that you can set the resolution and refresh rate (and he also hacked in a framerate adjuster). So by pressing ctrl+h you get half resolution and by pressing ctrl+q you get quarter (ctrl+f sets it all back). Ctrl+1-5 adjusts the framerate of the video card. This only works on games that used a 3dfx card, so afaik fighters don't fall into that group.