SYS_FAN1 says pin1 = GND and pin2 = 12V.
I only measure 7.72 V, resulting in a fan (3 pins) speed of 550 RPM i.s.o. #1000 RPM.
The BIOS doesn't show any settings to be modified in order to change voltage on SYS_FAN1.
Ok. Thanks. I noticed only now that in fact the fan starts up with 380 RPM (cold PC) top 600 RPM after 5 minutes power up. Do I need the Gigabyte windows utility or is it also possible to manipulate the voltage of pin2 SYS_FAN1 using BIOS? I ask because if I don't use Windows (e.g. Ubuntu), am I also able to change the voltage?