The pin helped sometimes but there were a few arrangements that fit but did not work. Female DVI to Female VGA adapters existed for going from VGA to DVI-A but

The pin helped sometimes but there were a few arrangements that fit but did not work. Female DVI to Female VGA adapters existed for going from VGA to DVI-A but this meant you could fit a pinless DVI-D cable and a VGA cable together this way.