Hi! Here is my "cheater" build for the Fractal Terra case:
Components
Case: Fractal Design Terra
CPU: AMD Ryzen 7 7800x3d
GPU: RTX4080SUPER with Bykski water block
PSU: Corsair SF1000, 1kW
Mainboard: Asus Rog Strix B650E-I Gaming Wifi
Sound Card: ESI MAYA44ex
External Cooler: Mo-Ra IV 400
I designed and 3d printed a carrier for the sound card, which is now piggybacking on the water block of the GPU. It is connected to the Mainboard via a M.2 breakout cable and M.2 to PCIe-adapter. I get 1ms latency in Guitar Rig 7.
The water cooler is controlled and powered by the mainboard via a breakout module, which connects to the PSU and the pwm outputs of the cpu fan and aio connectors on the mainboard.
The whole setup is entirely inaudible even under full load (like rendering in Blender3d).
Edit: corrected a typo: it's a 4080Super, not a 5080
How well do those external fittings work? Do the air bubbles filter out relatively quickly? The highest point looks like it's your video card so I guess if it's last in the loop any air bubbles should get pushed out/stuck in the hump.
The fittings work reasonably well. There are always a few drops of coolant when I disconnect them, so I wouldn't use them with colored coolant and keep a paper towel nearby, but otherwise they're leak-proof.
It's usually enough to let the pump run at 100% for a few seconds to drive out any bubbles. It's pretty strong, I normally run it 40-50%.