Quote from: lightfoot on February 01, 2014, 07:03:33 PM

Quote from: raskul on February 01, 2014, 05:47:58 PM

Quote from: Gazza1 on February 01, 2014, 05:46:11 PM

How loud are those high power server power supplies?

imagine a jet engine taking off. Cheesy

Fan noise is usually caused by the blades stalling in the air. Reduce the speed a bit and the noise should go down a lot with a minimal reduction (and in some cases an increase) in airflow.

I've found this on my BFL singles; lowering the speed of the output fan slightly will really reduce the noise because at full speed it's simply stalling against the end holes and trying to pull more air through the unit.

Larger fans are much easier to keep quiet. Small high speed fans are just plain old loud. Slowing the speed reduces noise, but most are still very jet sounding like.