I will have the pumps, rads and fans in an enclosure sitting on top of my 'concoction' (search hint), in order to test some ideas and give me some 'elbow room' in my case whilst I plan out how to build mikeeputer rev3.0 (new case design from ground up to optimize case ergonomics, minimize heat and annoyances, and give me SPACE, and storage, etc). It will look like a piece of furniture to match my maple computer desk, allow me to stick the scanner on top and store other stuff) Very vague resemblance to a rackmount set up. (You would never guess that I don't do lan parties heh

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There will be one inlet and outlet for each loop running from this assembly (a polyethelene file storage case from office depot (no smirking, this is a prototype (as I look for the smirking smilie

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I want to get everything but the blocks out of there for now and see how much (or little as the case may be) fannage, etc., I can get away with. Combining loops will give extra capacity for dualies or 64 bit when it is affordable / mature enough for me.
The tubing run from this assembly to the blocks will be 2-2.5 feet at most for each loop. (Imagine 4 1/2" ID tubes running between the case and this assembly ).
The switchover between loops would happen at the blocks themselves, so no big new routing differences / problems