I agree with using externals to store your stuff. Wav files take up a heck of a lot of storage and just a few multi track recordings will soon slow down your PC. I have several externals of various sizes including a tera....they have come down in price over last few months..... handy for backup snd transporting stuff to and from different studios..... I also store some of the larger plugins and programs I seldom use to spare the O/S unnecessary work.

Some cards have a breakout box with a rack mount, and include preamps, XLR connectors, plus other balanced and unbalanced connections and phantom power. This is not really my area of expertise BUT I know a few guys who could give great advice if you need it.
A pal of mine who is also a studio engineer builds computers and has just made a custom studio PC from scratch for his home studio. It cost a fraction of the price and has the best parts and specs. I will ask him for a list of what is required.

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