That's pretty much it. OBS will record what is currently being displayed on your computer; games and such. A capture card will record from an external source like a game console or another computer.
That's pretty much it. OBS will record what is currently being displayed on your computer; games and such. A capture card will record from an external source like a game console or another computer.
In addition to what is said above, I believe using software recording consumes PC resources and processing power, while using a dedicated card should mean the load on the PC is minimal.