Their minimum RPM was ~1,000 RPM at ~50% and 0 RPM below that. When the Intel Skylake processors were released (I know you have a Kaby Lake CPU) we discovered that certain models of the Intel stock CPU cooler (Delta on the fan's label) were defective. If you run the FAN Test in A-Tuning on the CPU_FAN1 selection, do you get a full range (10% - 100%) of fan speeds? Meaning at 10% the RPM is not zero and the speed is below 1,000 RPM? I assume it is connected to the CPU_FAN1 connector at the top of the board. I'm not sure I completely understand the behavior of your various fans, so questions for you.įirst the Intel stock CPU cooler. At this point I would simply like to confirm that my basic assumptions that this board should control the speed of the fans whether three or four pins and if so I am obviously missing something.

Now I have explored letting A-Tuning control the speeds and manually controlling with the build in options in the UEFI and noting seems to change. A-Tuning indicates the 100% speed for the case fans is approximately 1500 and that at 50 degrees C where the CPU is idling the speed should be 60% of 3100 max (A-Tuning test) but it is not. Worse than that there is no effect changing from Standard to Full Speed in the UEFI. That said UEFI indicates the CPU fan is turning at 2200 plus and the two case fans at 1100 plus but jumping every 10 to 15 seconds to 2200 plus for a second or two and then back. I have interpreted that to mean if a three pin fan, they control speed with the voltage on pin 2 and if a four pin speed is controlled by the 4th pin using PWM The motherboard advertises that that the two case fan connectors (4 pin) have Smart Speed Control clarified with an asterisk, that they can auto detect if a 3 pin or 4 pin fan is in use. The Corsair Carbide Series 100 R Silent Edition case I purchased has two, three pin fans which may optionally be attached to a three speed control in the case or to the motherboard. Processor i5-7500 with stock Intel CPU Fan Completed new build early this week and having fan speed problems.īoard H270M Pro4 BIOS flashed with latest 4/2017 2

Asrock motherboard fan control