For what purpose do you need the gpu? If just wanting to get a screen for basic windows use, an older, less powerful card will work just fine, and are uber cheap. If wanting the gpu for more gaming purposes, that's a different story. Just saying you have a VGA is not a limiting factor. You can have 1024x768 vga or 800x600 vga , or even as low as 640x480. A card like a r9 380x or a rx 460 would be totally wasted at those resolutions.
So a little clarification would be nice , if possible