Hello Martin, I am sorry to hear that you are having this kind of problems on your motherboard.
The following article will give you information about this behavior, since it is totally expected when using a three wire fan connector.
The 4th pin is the one in charge of the fan control; therefore it is not working when using those fans on your chassis. Desktop Boards — Three-wire and four-wire fan connectors
Hi Martin, you are facing this problem because you have 3 pin FAN SINK. Please note for fan control you must have 4 pin FANSINK. Because the 4 pin is responsible for carying the FAN speed. details given below
Pin Four-wire fan support 1 Ground 2 +12 V 3 FAN_TACH 4 FAN_CONTROL
for resolving your issue buy a 4 pin FANSINK.
Thanks & regards,
thanks for this very fast response - now, everything is clear. I've misinterpreted the 3pin/4pin option. I'd call it p.e.b.c.a.k. ;-)
I knew, the CPU fan is only supported if connected with 4 pins, but I thought the rear and front fan are supported if 3 or 4 pins.