My issue it’s a non-issue, many people would say. I bought a beautiful metal case from KKSB for my C4, the fan its too noisy even for me (wife factor already downvoted this option) so as a workaround I remove the fan and went fanless. Cannot complain, ondemand settings give me between 48-51 C.
The fan is powered at 5V.
I see a hardware solution buying a fan powered at 3.3V (care to recommend a silent one if you have one in use).
Is there a way to throttle the fan speed (script from autostart.sh) so I can still use the fan from KKSB case? When I used that option the 30 C temp was interesting (now its ok with ambiental temp but in summer I have inside 27-30 C).