Though IBM always used DE-15 connectors for their Video Graphics Array hardware, several VGA clone hardware makers initially did not. Instead, some early VGA hardware, both monitors and graphics cards, used the PGC standard of a DE-9 connector for analog RGB (VGA).
In the very early days the 9 pin was used for video. The extra pins were added when VGA obtained Plug ‘n Play compatibility.
That was CGA/EGA, digital RGB
VGA has always been 15 pin D-sub, analog RGB
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