I was only using the term "dedicated" in the context of high end audio output from the PC. Sure, the consumer grade DACs supplied on motherboards are fine for games or watching videos, but they are built to a cost point that amounts to pennies in the overall build cost of the motherboard. They are not intended for audiophiles or pro audio users.
It seems reasonable to me to spend at least as much, or more, on an audio interface as I would invest in a motherboard. I am a hobbyist, and I work mostly in the box myself these days, having retired most of my external hardware to the storage closet. I bought an external audio interface over 10 years ago, and it still works fine. I consider that one of the best computer investments I have made, and it has served me over the life of 3 computers.
In addition, if you work with virtual instruments, the lower latency of the factory ASIO drivers used with pro audio interfaces should give you a more realistic experience while playing them.
Good luck with whatever you choose.