MSI B450 Tomahawk PWM fan control broke?

Nexus18 · 5 Jul 2020 at 11:45

Hi all,

After putting the newest bios on, I noticed that my fans weren't set for PWM so I have enabled smart fan control mode and the PWM mode, however, when using hwinfo, it seems like the fans aren't adjusting their speeds

The sys1fan is DC mode as it's only 3 pin but the sysfan 3 and 4 are akassa apache 120mm PWM fans

Nexus18 · 5 Jul 2020 at 15:02

PieEater said:
You need to put some load on the CPU so the temperatures rise and the fan speeds should pick up - your screenshot shows an average CPU temp of 33.2 which is below the minimum temperature you've set in BIOS (40c), until your CPU gets above 40c the fans won't ramp up.

Sorry should have explained it better but are the sys/case fans not running rather high considering the temps are low.

akassa apache should be able to drop to 600rpm iirc.

Also, the cpu fan shouldn't be running at that high of a RPM given it's temp?

Nexus18 · 5 Jul 2020 at 17:34

With CPU selected instead, still the same :confused:

Nexus18 · 5 Jul 2020 at 18:28

PieEater said:
Does your BIOS have a fan autotuning feature where it goes through and detects the fans charecteristics? Otherwise try setting to DC mode rather than PWM for fan control as this should definately work.

Not too sure abut that tbh.

I'll need to jump back into the BIOS later to have a look. But I think the above photo is the only thing I have with regards to fan controls.

I did try DC too but it also doesn't adjust the fan speeds.

Originally, the smart fan mode was disabled and DC was enabled and things appeared to work as they should in terms of the fans changing RPM, however, I thought PWM would have been better and having the case fans set to work with the system temps.

Relentless81 said:
Are they 20c out? I had that problem on my MSI carbon b450 but it was fixed in the latest bios update and only effected fans set to CPU

Basically the CPU temp was 20c out so 40c was 60c in reality so it looked like they weren't doing anything in windows, might be worth a check

Just had a look at the bios versions, I am one version out of date although no mention of that fix in the log but I'll stick it on anyway just in case.

Nexus18 · 5 Jul 2020 at 19:19

Newest BIOS update done and still the same :/

It's not a massive issue as temps are good and case isn't stupidly loud but still annoying how this doesn't seem to be matching up with the low temps.

Nexus18 · 6 Jul 2020 at 10:59

C64 said:
have you cleared cmos after bios update ?

Nope.

Will try that later today, thanks.

Nexus18 · 9 Jul 2020 at 18:59

VaderDSL said:
Not using MSI Dragon centre by any chance?

It's installed and running in the background but no settings are set, I only use it for changing the LED on my MB

Nexus18 · 9 Jul 2020 at 20:26

Checked there and couldn't see anything enabled/set for the fans, have also removed it too.

Nexus18 · 10 Jul 2020 at 11:04

When I switch to DC for the 2 akassa apache fans, they don't even show in HWinfo but they are running.... and look to be running at very low speeds :/

CPU fan still at mad RPM with DC though....

Nexus18 · 11 Jul 2020 at 14:49

Thanks all for the advice, I'll give this a shot this week.

Nexus18 · 22 Jul 2020 at 22:19

Well, using dragon centre works so I'll make do with it.

Thanks all.

Nexus18 · 23 Jul 2020 at 10:01

PieEater said:
It's great you managed to get a workaround but still frustrating you're not able to rely on the BIOS settings. It would seem that something in Windows was overriding the BIOS settings and Dragon Centre has been able to bypass that. I don't know how much hassle it is to set up Dragon Centre but now you've got the fans working it could be worth doing a full uninstall of Dragon Centre and using the registry cleaner in CCleaner (download the portable / lite version to avoid installing Avast) to make sure all unnecessary registry settings are removed, then see if the BIOS settings are retained in Windows with the idea to go back to software control if this doesn't work.

A PITA to reinstall too

I think you might be right though and that there is something from dragon centre over riding the default bios setting as when I tried to put it back on, the application would just finish the install and the install window closes straight away, no chance for me to click finish or anything and dragon centre still wasn't installed, installed revoo etc. to see if it was properly uninstalled the first time but I couldn't see anything.

The only way I could get it to reinstall was to do it through the windows store.

Happy enough for now plus I need dragon centre anyway to be able to change the RGB lighting on the MB

Nexus18 · 6 Sep 2020 at 09:48

And for some reason now it seems like dragon center is broke for CPU fan control, back to a ridiculous speed at idle/low temps....... :mad:

When I click on the CPU fan speed, it should pop up with another window to adjust the fan curve..... The case/system fans still work though.

Think I'm just going to chin of the MSI MB come next CPU upgrade and go with GB.

Nexus18 · 26 Feb 2021 at 13:14

Just to update this thread, still having issues with the fans not fully adjusting i.e. they just don't seem to want to drop below 1000RPM.....

Have got new artic P fans PWM too.

Nexus18 · 26 Feb 2021 at 16:43

ShivP said:
What software is that?

https://github.com/Rem0o/FanControl.Releases

Nexus18 · 7 Mar 2021 at 11:04

Ok this is weird now..... Seems the back case fan is adjusting as required but the front 2 still won't drop below 1000??? :confused:

Nexus18 · 8 Mar 2021 at 19:28

Just another update, seems using dragon centre fan control again has fixed the issue! Straight after some cyberpunk.....

Here's hoping it doesn't break again as system is lovely and near enough silent.