I have a PC with an i5 4460 chip and use the built in graphics. Where can I get a comparison between this and dedicated video cards? I have tried googling, but can't quite get exactly what I want. I know a GT 720 is just a bit better, but is it worth buying? I only play old games from way back and watch HD video.
It's difficult to directly compare integrated graphics to a low end dedicated card. You don't need a dedicated GPU for HD video. Depending on how old the games are, the GPU probably wouldn't help either.
From a price to performance perspective, I don't think it makes sense to spend money on a GPU unless you are going to get at least an R7 250x or GTX 750. Anything less costs way too much for the meager performance gains over integrated graphics.