Well that is a matter of your own definition of noiseless
The quietest 120 mm fan I have is a Papst 55 cfm model, I still prefer running it on 7 Volts to keep the noise level down, and it's not the fan noise - it's the rush of air that bothers me. I guess my radiator is making most of the noise through it's aero-dynamics.. sigh.
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Pump:Eheim 1048,
Radiator:LPD radiator 100x150x20mm,
CPU block:DD Maze-2,
GPU block: DD GPU block,
Chipset block:Zalman NB32
AMD XP 1500+, EpoX 8K7A, PoV GF3Ti200
Pic of my YY-cube