Speedfan - how to kick-start 3pin fans?

Control: management of fans, temp/rpm monitoring via soft/hardware

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Speedfan - how to kick-start 3pin fans?

Post by aerial » Fri Feb 22, 2019 3:01 am

I use speedfan fan control for bunch of 3pin DC fans on my watercooling radiator.
I have fan curve set in "fan control tab".
System is designed so that during idle and low load, fans are turned off, because there is no need for them to operate. They turn on initially when you start PC, but once speedfan loads upon system startup, fan curve starts to work, low temperature = fans turn off.

Now the problem I have is, fans require certain RPM to start, and that RPM is higher than their minimum operating speed. They also all work on same wire, connected via splitter, and they have slightly different starting speed. So I basically need to set first RPM step to speed of fan that has highest minimum starting speed. This way I ensure all of them start simultaneously.
Question is, is it possible to make fans start at that given speed and then go lower? Because I can manually start fans by typing in certain speed, and then once they start spinning, I can lower it quite a bit, and they will still operate. If I attempt to start them from 0 rpm right to that desired speed, they wont start, not enough power to start spinning. Speedfan doesn't allow me to change direction of fan rpm curve, it can only stay at same level or go up with increase in temperature on sensor. I also don't see any option that would help kick-start the fans.

I know it can be done if you set some low rpm speed in idle (so fans kick-start from that initial 100% RPM upon launching pc, and then speedfan lowers the speed).
But I want to have fans turned off in idle, then start with certain temperature reading from sensor, but go down to their real minimum rpm after they start spinning.

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