I'm surprised it did'nt improve it!, but then I'm only guessing without seeing the componants. I'd try them all on the pump and see which one 'shoots' water the farthest. That'll be the one with the most velocity. Whether it's the same submerged is beyond me though :shrug: ...
I agree!, Cathars latest block is very interesting!. Looks like one a competant homebrewer could make as well with basic tools

, it's the one I'd be concentrating on

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I don't know why I never thought of that before with the P4 h'spreader. It's something I've done myself with GPU chips, ignore the plastic 'package' and concentrate on the 10x10mm core in the middle. I've never put much thought into a Pentium core though. AMD all the way! (can't/would'nt afford a P4

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