questionson board video vs. video card?

vote-for4vote-against
vote-for1vote-against

That's a 2GB graphics card. Not that much older. Plus you wouldn't have to use any of the 8GB of system RAM to support the on-board video.

Especially if you aren't playing any new games. Both are very adequate, but going with add-in will free up some RAM for you.

vote-for1vote-against

For general use, the add-in card would be a best, unless your video editing absolutely fills up its available memory.
Also, if you pop in the card, you should be able to enable/disable either to perform a comparison; I would say this exercise would be worth your time.