Internal Soundcard v External Soundcard v Audio Interface

Hey Logan, I've been wondering as I have been researching a lot for this setup I'm saving up to have three years from now. Technology will change drastically of course and new things will come so my shopping list will change as the 3 years go by (planning to spend $14k to $18k on my setup). I have one thing that has bugged me the most at the moment. All other things I have researched for has provided good answers and solutions. This particular one has not. I wanted to know what has better features and overall gives off better sound for studio monitors, subwoofers, and high end open headphones? Internal Soundcards like the Asus Xonar STX, External soundcards, or Audio Interfaces like the Native Instruments Komplete Audio 6? If it's too much to fit in the INBOX.EXE episode, could you make a separate video or video series? Your recommendations for best ways to enjoy audio has been greatly appreciated for headphones.

(planning to spend $14k to $18k on my setup)

Anyways all I know about audio is my $40 mobo has shit audio so I am getting myself an Xonar DGX or something.

Lol by setup I don't mean by just the PC. Like the studio monitors, keyboard (for music 61 key), lots of software, etc. included along with the PC which would cost $4k-$4.5k

I don't need a $14k-$18k PC xD

You scared me for a second there

If you are going to be recording and tracking/mixing/producing music I would look into Presonus Audio Electronics. They make very nice audio interfaces in USB and Firewire and at very reasonable prices. They also recently launched a series of studio monitors that are blow your socks off awesome. Check out Eris E8 Monitors and StudioLive mixing consoles. Full digital but with that old school analog feel in the layout. I have owned several pieces of their gear and I use their software Presonus Studio One for mixing and recording. I have never found anything better software wise. I have know many pros that have left ProTools and Cubase to use it. All around great company.

P.S. The Presonus users community is also one of the most helpful and friendly communities I have ever been a part of.

That's exactly one of the many things I will be doing with my pc and setup. :) Thank you very much for those recommendations.

You are very welcome. I hope the information helps. =)