Motherboard (BIOS) doesn't see a working case fan plugged into 3pin header.

[colovianfurhelm]

Hi!

I have a bit of a problem here.

I bought three case fans, which are connected to the motherboard.

All of them are 3-pin.

Two of them are connected to 4-pin headers and work quite slowly without load (have not tested in games), but are configurable in BIOS, etc.

 

One is connected to 3-pin header, runs at full speed, and is NOT seen in BIOS or by software.

 

The motherboard is Gigabyte Z170-HD3.

The fans are Corsair SP120 RGBs.

What can be the problem here? I don't like the fan running at full speed.

 

I exchanged the connections, and it showed that the fans are not the problem - the 3-pin header is. 

[W-L]

1 minute ago, colovianfurhelm said:

Hi!
I have a bit of a problem here.
I bought three case fans, which are connected to the motherboard.

All of them are 3-pin.

Two of them are connected to 4-pin headers and work quite slowly without load (have not tested in games), but are configurable in BIOS, etc.

One is connected to 3-pin header, runs at full speed, and is NOT seen in BIOS or by software.

The motherboard is Gigabyte Z170-HD3.

The fans are Corsair SP120 RGBs.
What can be the problem here? I don't like the fan running at full speed.

It depends on the board, some don't allow for speed control and are just power header. You can get a splitter to group control two fans together and configure it for 3 pin, DC voltage fan control. 

[Colin Donoghue]

3 pin connectors do not have a fan controlling wire and will just power the fan

[colovianfurhelm]

But why are they controllable through 4 pin header, if they are connected only to three of the pins?

[W-L]

1 minute ago, Colin Donoghue said:

3 pin connectors do not have a fan controlling wire and will just power the fan

You can control 3 pin fans via DC voltage control, it just needs to be configured if it is a option within the board. 

 

Just now, colovianfurhelm said:

But why are they controllable through 4 pin header, if they are connected only to the three of them?

The header is configured as DC voltage control, some boards just physically do not have the function built in to control every single fan header and leave some as full 12V power. 

[colovianfurhelm]

I see.
So if I find the Y-splitter, it should be 4-pin to 2x4pin/2x3pin, right?

[colovianfurhelm]

I just find it pretty weird that I can't even see the stats of the 3pin-connected fan, as if it doesn't exist at all. Pretty confusing.

[m0k]

9 minutes ago, colovianfurhelm said:

Hi!

I see three 4pin fan headers on your mobo - unless its a different revision

 

I usually get the Noctua 4pin fan splitter and connect two fans to a single 4pin header, works fine, gives me control

[colovianfurhelm]

1 minute ago, mok said:

I see three 4pin fan headers on your mobo - unless its a different revision

 

I usually get the Noctua 4pin fan splitter and connect two fans to a single 4pin header, works fine, gives me control

Because one of them is for CPU, the rest are 2x4pin and 1x3pin (SYSFAN_3 that is not visibile in BIOS)

 

Thanks, I'll have to look for a splitter, then.
Is it safe to use? 

[m0k]

Just now, colovianfurhelm said:

Because one of them is for CPU, the rest are 2x4pin and 1x3pin (SYSFAN_3 that is not visibile in BIOS)

 

Thanks, I'll have to look for a splitter, then.
Is it safe to use? 

yeah thats when im doing on my ancient Gigabyte 890FXA-UD5 motherboard, i only have 2 4pin headers on the mobo

https://www.amazon.ca/gp/product/B00KG8K5CY/ref=oh_aui_detailpage_o09_s00?ie=UTF8&psc=1

 

i dont like how loud 2 of my case fans run at full speed (1200 rpm) so i hooked it up to the 4pin headers and now they run much quieter at 800-1000 rpm

[colovianfurhelm]

Will it work for 3-pin fans? 

I don't really get whether my 3pn fans, which are connected to 4pin, are controlled by the motherboard or not. I can configure them in BIOS and software, but will they do so automatically according to the temperature curve, as for example Gigabyte SIV seems to suggest.

[W-L]

Just now, colovianfurhelm said:

Will it work for 3-pin fans? 

I don't really get whether my 3pn fans, which are connected to 4pin, are controlled by the motherboard or not. I can configure them in BIOS and software, but will they do so automatically according to the temperature curve, as for example Gigabyte SIV seems to suggest.

The header has to be setup as DC voltage control for 3 pin fans for it to vary the speed which it probably is currently if it's changing speed during load.  A regular fan splitter like the Noctua one or any regular one will work.

https://www.amazon.com/SilverStone-System-Cables-Black-CPF04/dp/B00B46XKKQ/ref=pd_lpo_vtph_147_bs_img_2?_encoding=UTF8&refRID=1ZVP3VDE69BNK1PC0FYA&th=1

[colovianfurhelm]

Just now, W-L said:

The header has to be setup as DC voltage control for 3 pin fans for it to vary the speed which it probably is currently if it's changing speed during load.  A regular fan splitter like the Noctua one or any regular one will work.

https://www.amazon.com/SilverStone-System-Cables-Black-CPF04/dp/B00B46XKKQ/ref=pd_lpo_vtph_147_bs_img_2?_encoding=UTF8&refRID=1ZVP3VDE69BNK1PC0FYA&th=1

I've read that when using two fans on a single header via a splitter, I have to make sure that the voltage for both fans summarized should not exceed 12v. How do I do that? 

[W-L]

5 minutes ago, colovianfurhelm said:

I've read that when using two fans on a single header via a splitter, I have to make sure that the voltage for both fans summarized should not exceed 12v. How do I do that? 

That's not something to worry about the headers can only provide a max of 12v, you just want to make sure you don't exceed the amperage the header can provide which is usually 1amp. A good rule of thumb is no more than 3-4 fans per header. 

[colovianfurhelm]

I see, thanks!

Last question.

Is it a viable alternative to the Y-splitter?:
 

Buy the ASUS STRIX 10-something videocard (I need a GPU anyways) which has its own 4-pin connector for a case fan, and use that header for this problematic fan, which incidentally sits exactly where it will blow on the GPU. 
Seems to check out for me, at least.

[W-L]

1 minute ago, colovianfurhelm said:

I see, thanks!

Last question.

Is it a viable alternative to the Y-splitter?:
 

Buy the ASUS STRIX 10-something videocard (I need a GPU anyways) which has its own 4-pin connector for a case fan, and use that header for this problematic fan, which incidentally sits exactly where it will blow on the GPU. 
Seems to check out for me, at least.

You can't use the header on a GPU for a case fans they physically aren't the same as the GPU uses a mini fan connector. 

[colovianfurhelm]

Just now, W-L said:

You can't use the header on a GPU for a case fans they physically aren't the same as the GPU uses a mini fan connector. 

No, no, I mean the FanConnect feature - 2 additional 4-pin headers on the GPU.

[W-L]

Just now, colovianfurhelm said:

No, no, I mean the FanConnect feature - 2 additional 4-pin headers on the GPU.

Oh dedicated connectors like those, yeah you could set them up with that header there to control the fans but it will have to be through their software. 

[colovianfurhelm]

Yeah, seems like a solution to me. Thanks for the answers!