I used my telephone wires as pull strings to wire every room in our house. Since every room had at least two cable jacks, piping cable from the outside “cable box” to a “network closet” was a breeze. Just add a patch panel, your modem, and router, and then you’re set. I needed an extra 8 port switch, but ymmv.
I have a telescope that uses a CAT 5 crossover cable, but it is NOT ethernet. Two pins are 12 volt power, and other pins tell the motors which way to slew, and report back to the controller how far they’ve traveled.
Look at the pinout, but unless it’s talking ethernet, you’ll need two cables to do both.
Fractal Design 7 can easily hold more than eight, but you’ll need more fans and trays.
Stuff