03-09-2020, 11:29 PM
(03-09-2020, 12:45 PM)Nikolay_Po Wrote: Just for record. Yesterday I started second server based on RockPro64. And I'm hearing audible noise. My first server is still working right in front of me and I'm not hearing any sound. But second server produces noticeable amount at 0.3m distance. At 0.5m distance the noise is not noticeable.
Tried to touch suspicious components. And it seems to me the nose is going not from inductors but from ceramic capacitors. C2005 or C2012, which is closer to power jack. And the noise is depending on CPU mode of operation.
Guessing the silent server Linux distributive keeps CPU cores on and at single speed. A distributive with more aggressive power saving which is changing CPU core speed dynamically may produce more noise due to larger change of supply currents. But this is just my thoughts, have not checked yet.
Strange that capacitor make noise, normally should be inductor.