Question Case fans not following BIOS custom fan curve after booting to Windows

[fromage123]

Cross-posted from the Cases subforum as it's probably more relevant here.

So I've recently built a new PC with a Gigabyte B660M DS3H AX motherboard and Tecware Forge M case which comes included with these fans: https://www.tecware.co/_files/ugd/8517ed_0747040c92ab489ea41d89de8fab8408.pdf.

I've set up a custom fan curve in the BIOS for the CPU and case fans but the case fans do not seem to follow this. I am not getting a RPM reading from the case fans either but I believe this is because the cable connecting the fan hub in the case to the motherboard doesn't have sufficient pins (it is 3 pin and missing the "Sense" pin).

Now in the BIOS menu the custom fan curve is being applied to all fans, it's only when I boot to Windows 11 that this is being overidden and the case fans go back to their defualt settings. As far as I am aware, I don't have any additional software that should be affecting the case fans.
I'll attach some photos of the cable from the fan hub to the mobo, the case fan remote, and the settings I'm using in the BIOS.

View: https://imgur.com/a/uWZnR7v

I've done some experimenting with these settings and it's a bit weird. In terms of BIOS settings - as you can see from the picture this is how I've set it up.

• With these specific settings, in the BIOS menu I can control the case fans. The "Control Mode" has to be set to PMW - both Auto and Voltage don't work and the case fans resume to their default speed.
• In terms of the remote - this must be set to "Fan Auto" for the BIOS settings to control the case fans, "M/B sync" only seems to affect the RGBs and "Fan +/-" changes the default speed of the case fans (either can be slow or fast). No other buttons seem to affect the fans.
• If I boot to Windows with these BIOS settings, the case fans reset to their default speeds.
• If I boot to Windows with "Control Mode" set to Voltage the case fans turn off (RGB still works)
• If I boot to Windows with "Control Mode" set to Auto nothing changes as with these settings the case fans are still at default speed in BIOS menu and remain so after boot up.

Any help will be really appreciated.

 

[Darkbreeze]

Your hub is the problem. Bypass it and connect your PWM cables directly to the motherboard headers. You can't connect a 3 pin hub to a 4 pin fan header on the board and expect it to properly control 4 pin PWM fans connected to your hub. You may need to get one or more PWM cable splitters if you have more than three case fans since your board only has three PWM system fan headers and one CPU fan header on it. You can still connect your RGB cables to whatever you were already using to control the lighting as those are entirely separate circuits on the fan.

 

[fromage123]

But if that were the case then how come I can control the speed in the BIOS menu? It's only when I boot to Windows that it stops working. From all my research most people seem to say it's fine to plug 3 pin fans into a 4 pin header and it should still work, I've even found a youtube video where he has it working on a different mobo (but still with 4 pin headers) - the fan's are slightly different but the hub is the same:

View: https://www.youtube.com/watch?v=t0gdrIHI3Do

 

[Darkbreeze]

See, you are confusing yourself.

There is nothing wrong with plugging a 3 pin fan into a 4 pin header, fan will work, even on older boards, but it will run usually at full speed. On newer boards, you can plug EITHER a 3 or 4 pin fan into ANY of the headers on the majority of boards now and they are able to be controlled BUT you need to do two things.

One, you need to assign that header as either DC (3 pin) or PWM (4 pin) in the BIOS, AND you also want to make sure that the "source" for the thermal response is the "motherboard sensor". Not the CPU. Not anything else. Well, occasionally SOME people choose to use the GPU or VRM sensors but in generally you usually want to make sure any case fan is using the motherboard sensor, which is a combination of the readings from multiple sensors, for speed control.

Hubs introduce a totally different set of problems into the equation because for the most part none of them work with both PWM and DC controls. Or if they do, they do so in a limited fashion. There are a few that work but they STILL don't work entirely correctly and in many cases they will work but can be eventually damaging to fan motors.

I don't really have time at this moment to get into it all because it CAN get rather complicated, but your best best here is probably to see if @Paperdoc might be willing to chime in because he is a very experienced user in these matters and is also able to easily explain things in a way that usually even the layman can understand. And now that I posted that, he'll be aware of the shout out and should chime in IF he feels like he wants to. He's usually really good about helping out in these kinds of threads.

 

[kuhne]

Maybe go for one of those internal usb fan hubs? Like the ones some liquid cooling pumps come with ?

 

[fromage123]

See, you are confusing yourself.

There is nothing wrong with plugging a 3 pin fan into a 4 pin header, fan will work, even on older boards, but it will run usually at full speed. On newer boards, you can plug EITHER a 3 or 4 pin fan into ANY of the headers on the majority of boards now and they are able to be controlled BUT you need to do two things.

One, you need to assign that header as either DC (3 pin) or PWM (4 pin) in the BIOS, AND you also want to make sure that the "source" for the thermal response is the "motherboard sensor". Not the CPU. Not anything else. Well, occasionally SOME people choose to use the GPU or VRM sensors but in generally you usually want to make sure any case fan is using the motherboard sensor, which is a combination of the readings from multiple sensors, for speed control.

Hubs introduce a totally different set of problems into the equation because for the most part none of them work with both PWM and DC controls. Or if they do, they do so in a limited fashion. There are a few that work but they STILL don't work entirely correctly and in many cases they will work but can be eventually damaging to fan motors.

I don't really have time at this moment to get into it all because it CAN get rather complicated, but your best best here is probably to see if @Paperdoc might be willing to chime in because he is a very experienced user in these matters and is also able to easily explain things in a way that usually even the layman can understand. And now that I posted that, he'll be aware of the shout out and should chime in IF he feels like he wants to. He's usually really good about helping out in these kinds of threads.

Thanks for your replies so far but it feels like we're talking past each other a bit. Do you understand that I am able to control the fans in the BIOS menu? i.e. the fans are following ym custom fan curve in the BIOS menu.

 

[Paperdoc]

Darkbreeze, thanks for the shout-out, it DID get to my attention.

First, in this situation OP has a set of fans with NON-standard cables and connectors, so there is NO good way to use a different Hub or to plug any of these fans into mobo headers of any type. OP really does have to use the Hub and its features.

OP, you are right about the speed display. There is no wire in the cable from the Hub back to the host header to convey the speed signal (mobo header Pin #3), so the mobo will never "see" that info. Regarding the ability to CONTROL the speeds of the fans on that hub, the Hub CAN use the PWM signal from your mobo SYS_FAN header to do that. As you recognize and as Darkbreeze said, that header MUST be configured to use the "Normal" Fan Speed Control and the "PWM" Fan / Pump Control MODE settings. Your dilemma, if I read correctly, is that this seems to work in BIOS Setup but then fails when Windows boots, leaving you with all fans at full speed. My suspicion is that this is caused by the Hub. I suspect that, on any boot up, the HUB resets itself to a default setting that includes using is OWN fan speed control. THEN you have to use the manual remote control box button to set to the Fan Auto configuration to tell the Hub to allow the mobo header signal to take control. A little inconvenient, but this needs to be done after every boot-up.

 

[fromage123]

Darkbreeze, thanks for the shout-out, it DID get to my attention.

First, in this situation OP has a set of fans with NON-standard cables and connectors, so there is NO good way to use a different Hub or to plug any of these fans into mobo headers of any type. OP really does have to use the Hub and its features.

OP, you are right about the speed display. There is no wire in the cable from the Hub back to the host header to convey the speed signal (mobo header Pin #3), so the mobo will never "see" that info. Regarding the ability to CONTROL the speeds of the fans on that hub, the Hub CAN use the PWM signal from your mobo SYS_FAN header to do that. As you recognize and as Darkbreeze said, that header MUST be configured to use the "Normal" Fan Speed Control and the "PWM" Fan / Pump Control MODE settings. Your dilemma, if I read correctly, is that this seems to work in BIOS Setup but then fails when Windows boots, leaving you with all fans at full speed. My suspicion is that this is caused by the Hub. I suspect that, on any boot up, the HUB resets itself to a default setting that includes using is OWN fan speed control. THEN you have to use the manual remote control box button to set to the Fan Auto configuration to tell the Hub to allow the mobo header signal to take control. A little inconvenient, but this needs to be done after every boot-up.

Hey man thanks for replying and undertsanding my problem.
The Fan Auto button definitely has a role as it needs to be on for the custom curve to take effect in the BIOS menu.
Unfortunately the Fan Auto button doesn't help once Windows has booted. With the default speed settings there are 2 - slow and fast. If I press Fan Auto when it's slow it speeds up to fast and if I press it when it's fast it does nothing. I've tried the fan button on the hub itself and this has the same effect.
In fact I don't believe it's resetting to a default state on Windows boot but rather something else is telling it not to follow the fan curve but instead use the default high speed state.

 

[Darkbreeze]

This is such a common problem on cases that come with proprietary fans. Screw that. Your best bet, honestly, is to simply buy aftermarket STANDARD compliance fans. Whether DC or PWM is up to you, but anything other than proprietary ones. We see this on some of the OEM stuff and a few of the Corsair products among others. My recommendation if it's a proprietary fan is always the same, replace it. Throw it away. Because in addition to the fact that they never seem to play nice with anything, once that fan hubs dies, and it will, you will have to buy new fans anyhow because you aren't going to find a replacement hub that works with them unless you buy another identical case or are able to source the hub directly from the case manufacturer as a replacement part, which is doubtful if you're not talking about one of the big brands like Corsair, CM, Thermaltake, Fractal Design, etc.

 

[Paperdoc]

OP, try this. Your fans do NOT say anything about this, but many such fan hubs work this way.

On the Hub, go to the Fan Speed button. Push that and hold it in for at least 5 sec. This MAY be the command to turn over control to the outside signal.

Try that also with the remote's Fan SPEED button.

 

[Darkbreeze]

I wish companies would just stop it with the proprietary crap. There is literally no reason or need for it other than to make you beholden to them, if you're not wise enough to simply ditch their cheap integrated hardware, in the event something quits working. Doesn't matter if it's a fan or the hub, if something quits working then basically anything aftermarket isn't going to work in it's place, at least, not easily. There are perfectly good DC and PWM standards, and perfectly good RGB and ARGB standards, and no reason for them to do this stuff anymore.

But, I also get it that if you already have the hardware might as well use it UNTIL something craps out, so I'd try what Paperdoc suggests. He's usually spot on or pretty close to it when it comes to fans and controllers.

 

[fromage123]

Hi both, thanks for your replies. I've tried all the suggestions so far but still not working so it looks like I'll have to get some new ones unfortunately. If you have any recommendations of 'cheap' 4 rgb fans plus hub that would be really appreciated but I'll be complaining to Amazon about this anyway to see if they can help.

 

[DRagor]

As far as I am aware, I don't have any additional software that should be affecting the case fans

You may not be aware and still have such software installed. Particularly if you installed any of the Gigabyte apps that come with motherboard then you surely can have something that can mess with the fans whether you want it or not.

 

[Darkbreeze]

So, those fans are so cheap the "manual" doesn't even say if they are 120 or 140mm fans. What size are they?

 

[fromage123]

I ended up just returning the case and will be getting a new one - MSI MAG Forge 100R, hopefully the fans in that won't have the same issues. Thanks again for the help.

 

[Paperdoc]

That new case comes with a couple of lighted fans for the front, and one unlighted for rear. All use "standard" connectors so you CAN plug them into mobo headers. All the fans' motors are of the newer 4-pin PWM style, so no problems there. The case even includes one 1-to-3 Splitter for fan motors so you can use that to connect up to three front fans to one SYS_FAN header. You can use the mobo's standard fan speed control system for these.

The Lighted fans, like most "standard" ones now, come with TWO cables. One is for the motor only, and ends in a standard 4-hole female fan connector. The other is for the lights only and ends in a wider female connector with a (4-1) layout - it looks like it had 4 holes but one is blocked off. Because the lighting type is Adddressable RGB (ARGB), all of these need to connect to the D_LED header on your mobo (NOT the LED_C one). For that you may need to get an ARGB Lighting Splitter to connect several fans' lighting cables to a single mobo D_LED header. You can use the MSI software utility Mystic Light to power and control the lights connected to that header.

 

[fromage123]

That's great, thanks for the info. I don't think it has a fan splitter included though does it? I've not seen that written anywhere, not that it matter because I can just use all the fan headers on the mobo. It does have a 1-to-6 ARGB splitter included though.

 

[Paperdoc]

You are right, you have three SYS_FAN headers for connecting case ventilation fans. If the case really does include one 3-output Splitter, you can handle up to 5 case fans that way. Any CPU cooler system will connect to the CPU_FAN header. The fact it comes with that ARGB Splitter I did not notice, and that completely handles your needs there, I think.