Domenico use other fan becouse he has a very extreme Groove, so he needs the fan and power supply he used.
and passive fanless CPU coolers are heavy and not good as the one with fan. The most powerd mixers and amplifiers have built-in fan. fans has no effect on MS sounds. The MS has two power supply. 1 with fan for PC parts and 1 fanless for audio Parts
correct on groove we use the last generation of ATX power supply, with 14Cm Fan LOW speed. The CPU fan on the quad core is the same that you see on the picture, 10Cm Fan and is running from 650 to 2500Rpm, totally LOW noise. On the groove system you can hear more the HD heads that the CPU and ATX fan.
On MS is installed one 8Cm fan 3500 Rpm, make more noise BUT is one aceptable compromise.