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Can't adjust CPU FAN speed?!

commy
Level 7
Hi guys,

I am having slight problems controlling my CPU fan. In FanExpert it shows me the minimum and maximum speed as the same.
This makes the AiO quite loud at 2175 rpm (see screenshot).

System:
Windows 11
Z690 Hero (BIOS 2204)
AiO: Alpenföhn Gletschwerwasser 360 high speed (connected to CPU_FAN as well as AiO_PUMP)
The case fans (5 pcs.) hang on a fan hub from the Fractal Meshify 2 RGB case. The case fans can be controlled with FanExpert.

But the Alpenföhn unfortunately not... have also tried with AI Cooling but so far my attempts have been without success. I can only regulate more up.
Even the CPU fan profile "Quiet" is quite loud when sitting right next to the PC.

Did I miss something?


Thanks in advance!
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6 REPLIES 6

JohnAb
Level 17
You might have the same situation as myself. My AIO is USB controlled, but there is also a single wire running to the CPU fan header. This makes the CPU fan header see the speed of the pump, but it cannot be controlled by the motherboard or FanExpert (as there is only a single wire). See picture attached.

So basically, if you just have that single speed sensing wire plugged into the CPU fan header, that's the reason. A quick look will confirm.

If your fans are noisy, it won't be the CPU fan as I don't believe you have one. Pumps don't normally make much noise unless there is air in the system, so look for other fans that you can change. It might be the AIO radiator fans, in which case there might be software for your AIO which you can download?
Z690 Hero, 12900K, BIOS 3501, MEI 2406.5.5.0, ME Firmware 16.1.30.2361, 7000X Case, RM1000x PSU, ASUS TUF OC 3090TI, 2 x 16GB Corsair RAM @ 5200MHz, Windows 11 Pro 23H2, Corsair H150i Elite AIO, 4x Corsair RGB fans, 3x M.2 NVME drives, 2x SATA SSDs, 2x SATA HDs.

Hi there!

My Alpenföhn AiO is not controlled by USB.
I have a separate 3 pole cable for the pump, which is connected to the aio_pump header.

The 4 pole pwm cable of the fans on the radiator is connected to cpu_fan.


No success until now to change the rpm in Bios or FanExpert :(Â*

Update:

I Connected the pump not to the AIO_PUMP header but to CPU_FAN.
The fans of the radiator from CPU_FAN to CHA1. So that's how you do it on boards without an extra pump header.

My thought was simply that I can control the other 5 case fans via CHA1, so it should also work with the fans on the radiator.

Unfortunately I can not control the fans on the radiator.

Can not explain this behavior yet. Have it a week ago a similar system built with Asus board but on the AM5 platform. Which worked fine.

... maybe it's still an idea to connect the fans to the fan controller on the Fractal case?!

JohnAb
Level 17
Ah, sorry. I assumed your AIO would be connected by USB like mine. Strange if the other system worked. I think you'll just have to try some different connections then like you suggest. I can't see any reason why you shouldn't connect the AIO fans to any motherboard header, or the fan controller - whatever works. I'm not aware of any reason why you should be struggling. Have you tried adjusting the fans directly in BIOS as well (if connected to a motherboard header). At least you would know if the chosen header is working properly. Sounds like you'll just have to try different combinations. Other than that, I'm struggling to think of any clever ideas 😞

I'm assuming that the AIO radiator fans can be controlled and are not just fixed speed? Seems unlikely.

You might also try uninstalling Armoury Crate (there is an uninstaller on the support pages) and then try installing it again. Perhaps that might get FanExpert working properly? Do a reboot after installing it again, even if it doesn't ask you to.
Z690 Hero, 12900K, BIOS 3501, MEI 2406.5.5.0, ME Firmware 16.1.30.2361, 7000X Case, RM1000x PSU, ASUS TUF OC 3090TI, 2 x 16GB Corsair RAM @ 5200MHz, Windows 11 Pro 23H2, Corsair H150i Elite AIO, 4x Corsair RGB fans, 3x M.2 NVME drives, 2x SATA SSDs, 2x SATA HDs.

OK, problem solved 🙂

I have now removed the cable from the manufacturer which one connects the three fans to the radiator (daisy chan cable) and connected all three fans directly to the fan hub of the case.

And there is it... I get the PWM signal and can regulate the fans. Finally, no more jet on the table 😄

The supplied cable has 4-pins, but after the first fan it continues with only 3-pins. One pin is missing but not the PWM pin, but the one for the tacho signal. I don't know if this is the problem. Should not actually be, otherwise the Internet would be full of problems with Alpenföhn coolers? But something does not want the ASUS board with that cable.

I have now decided to install the ASUS bloatware, Armoury Crate. Madness how much services get installed with. I'm not a fan of it, because I prefer to control it directly via the BIOS. But the funny thing is that when I start the Q-Fan diagnostics in the BIOS, I get different results than with the Armoury Crate software. With the software I can turn down the fans a little bit more. I don't really understand either but as long as that fits now....

JohnAb
Level 17
Pleased you got it sorted commy. You can enjoy your PC at last 🙂
Z690 Hero, 12900K, BIOS 3501, MEI 2406.5.5.0, ME Firmware 16.1.30.2361, 7000X Case, RM1000x PSU, ASUS TUF OC 3090TI, 2 x 16GB Corsair RAM @ 5200MHz, Windows 11 Pro 23H2, Corsair H150i Elite AIO, 4x Corsair RGB fans, 3x M.2 NVME drives, 2x SATA SSDs, 2x SATA HDs.