Long ago at the height of madness I was running phase change on the CPU (Xeon X3220, basically a server binned Q6600) and a custom loop with dual D5s, dual 360mm radiators (with thick high static pressure Panaflo fans) cooling all 3 8800GTXs and the 780i northbridge on the motherboard. It was... Stupid. All that built in to a Lian-Li PC-V2000B Plus II with a 1KW PC Power & Cooling PSU and 4 7200 RPM WD Blacks in RAID 0. Living dangerously.
It took a long time to get that bad - I bought a bunch of used AquaComputer water-cooling stuff off the forums I used to frequent and managed to cobble together a cooling loop for one of the then 2 8800 GTXs, then I built a second loop for the CPU, then that got moved to the GPUs and expanded when I got the phase unit.
It was a lot of fun, and part of me really misses all the tinkering, but the other much louder and more reasonable part of me that's nearing 40 wants nothing to do with any of it and reminds me the monstrosity had to be plugged in to two different 20 amp circuits in the house (one for the phase unit, one for the PSU) or it would pop breakers.
I do wish I could find pictures - like 99% sure some have survived on an old hard drive somewhere, but brief searches when I'm feeling motivated over the last few years have come up with nothing.
I get your point too.
But the assembly and maintenance still put me off. I love building PCs, but the technicality of designing a loop is a bit too much DIY for my taste.
There's little to none in a larger case.
Basically any CPU block that fits. Same with the GPU block. As much radiator as you can fit/afford. One Liang D5 if it's one or two blocks and one or two rads, 2 if it's more than 2 blocks and 2 rads. Soft tube and compression fittings cause we're adults and don't have time for nonsense. Get a pump/res combo if you have space, run a fill port with the longest upright tube to it you can fit if there's no space for a res. People overcomplicate this stuff.
Now... Is it worth it? No. Not unless you value quiet far, far, far more than money. But it's not hard to figure out.