My second 1060 SC came back (first one was DOA) with the original bios. Updated to the 0db one for the full manual control of the fan.
Made a custom curve with Precision XOC and with Afterburner and works pretty great except of a small kink.
This is the curve:

The problem is that as soon as the temp hits 41 C , the fan ramps up to 100% for a second or two and then goes back to the value indicated from the curve.
This happens every time the fan stops completely. Upon the next time the card is under any significant load it spins up again to 100% just for a second or two.
It is pretty jarring to hear the fan come up so loudly.
Tried a second curve, this time keeping the fan to 25% up to 45 C, this issue happens then as well but now it only happens upon the first restart of the PC, during the automatic load of Precision/AB, because during POST the fan is as expected turned off.
After that, the fan spins up and down as expected.
It also happens if I leave the default curve in place and switch it to manual mode in any value, again spins up to 100% and then goes to the value selected.
Is this an issue with using a custom curve in general? Any tips on how to fix this ?
Maybe I should just open a ticket to get the original bios and be done with all of this tinkering :)