H170M-ITX/DL CPU fan control

So seems to be an improvement when in BIOS (1.60) I switch CPU Fan from Auto to 4-Pin.

I have an ASRock H81M-ITX and have just concluded a very frustrating day of intel stock cooler CPU fan speed control diagnosis.

Symptoms of the problem sound similar to those reported in this thread.
Erratic control of fan speed from whatever control source (one of the BIOS stock profiles, BIOS custom profile, SpeedFan 4.51 beta 4). A hunting behaviour of the speed. Fan wouldn't stay at a constant non-max speed.

Problem Intel cooler: NIDEC E97379-001
http://i.imgur.com/YOMgHFT.jpg

No problem (physically identical) Intel cooler: Foxconn E97379-001
http://i.imgur.com/tJw9bYW.jpg

CPU is Haswell i3

Just found new bios 1.70 (5/12/2016) with description

4. Modify CPU fan behavior.

I have tested but nothing changed. Fan speed control is still not working.  

Laukse wrote: Last week I bought the H170 Pro4, using it with an i5 6500 Skylake processor. Fanspeed is always above 2000, no matter what I do. A-Tuning fan-test reveals that less than 50% is not working for the cpu-fan. This is so sad, since I didn't buy new hardware for 9 years and now THIS...

iwik wrote: Just found new bios 1.70 (5/12/2016) with description 4. Modify CPU fan behavior. I have tested but nothing changed. Fan speed control is still not working.

The UEFI/BIOS update with this description, adds an option in the H/W Monitoring screen, just above the CPU FAN1 configuration settings.

That option is CPU Fan Type Setting. It's description on the right side of the screen states:

If using NIDEC made retail cooler,  please choose "4 Pin" option.

Both of you obviously have the stock CPU cooler with the NIDEC fan that seems to have a problem.

If you had read through this thread, you would have found that information already posted.

You would also have found that earlier, pre-Skylake stock Intel CPU coolers work fine on these boards, and all the 120mm and 140mm PWM fans I use work normally on the CPU_FAN1 header on my ASRock Skylake board.

iwik, did you configure this new option in that UEFI/BIOS update for your board? How did you do your test? If you did not configure this new option, then nothing will change, and nothing was tested.

BTW, I've contacted Intel about this situation, and we'll see what they say.

Laukse wrote: Thanks @parsec I didn't notice that it's already solved with this 4 Pin -option... Now everything works fine!

Thank you for your feedback!

We would like to know if this new option works with the Skylake boxed CPU coolers, or not. I thought another user said their results were not perfect when using this option. I'm glad it did fix your issue. Intel did not include a boxed CPU cooler with any of the Skylake 'K' type processors, so there are fewer of them in use and available for testing.

This situation is strange. PWM fan speed control has a defined specification that should (cannot!) be changed for one model of a PWM fan. Intel was the original designer of PWM fan speed control. If it was changed, all previously designed PWM fans would not function correctly.

That would make me think the board's PWM fan speed control was not working correctly. But the results when using other PWM fans, including the PWM fans on previous generation boxed (stock) Intel CPU coolers, are normal. All those PWM fans work fine with ASRock Skylake boards.

The only remaining explanation is the fan (NIDEC E97379-001 12V 0.28A) is defective on at least some of its production runs. I suppose it is also possible that the boards (or a subset of their production) have an issue of some kind, but that has NOT been proven. There is a post or two in this thread about some pre-Skylake boards that seem to have this problem. If so, why did that suddenly happen?