Since my warranty had already expired I've turned to more destructive approaches. Armed with a voltmeter, I spent my holidays poking around fans in quest for quiet. It turns out the bugger in red circle is connected to fans. It has the same voltage on it as all the fans. But most interestingly, it has voltage appearing and disappearing on it as the fans turn on and off!
BEFORE YOU CONTINUE READING, I MUST WARN - what I did will definitely void warranty, can possibly break switch or worse ( other switches, cause fire ). Proceed at your own risk.
For the sake of experiment i cut the wire showing fan on status. Turns out it makes the fans permanently on. They still change speed as before, but instead of turning off when switch cools they just stay at 3500 RPM with fans getting uninterrupted 6V (previously they dropped to 0V):
I'll leave it like this for a while to see if it fixes the dreaded on-off cycle, but i'll keep an eye on it to avoid any mishaps with stalled fans, temperature spikes, crashes or other potential problems.
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