Connecting multiple fans to a single fan header

[iddra7]

I have a Gigabyte GA-B250M-DS3H which has only 1 system fan header (4 pin), and of course 1 CPU fan header.

My case supports 4 120 mm fans.

From my understanding, I can actually buy 3 pin fans (they seem to be cheaper) and use a splitter to connect them all to the 4 pin header on the motherboard. I don't need to control them individually, I just don't want them to be running at full speed. Would this way my motherboard control the speed?

Basically, I just want to connect 4 fans to 1 header and I don't want them to be running at full speed.

 

[DRagor]

Yes, that is possible. However you need to make sure total power consumption of those 4 fans is not bigger then 1 A. Also, don't mix 3-pin and 4-pin fans on one splitter - choose either (actually best is use same model of fan). This motherboard will have no problem controlling all fans whether they are 3 or 4 pins (again, as long as you don't mix them).

 

[iddra7]

Yes, that is possible. However you need to make sure total power consumption of those 4 fans is not bigger then 1 A. Also, don't mix 3-pin and 4-pin fans on one splitter - choose either (actually best is use same model of fan). This motherboard will have no problem controlling all fans whether they are 3 or 4 pins (again, as long as you don't mix them).

Would something like this work even better?
The cables are long and it has a separate power connector.
But then in the description it says "5 x 4pin PWM" when in the pictures it looks like 4x 3 pin and a single 4 pin connector. I won't be using the single 4 pin.

 

[DRagor]

Yes, that is possible. However you need to make sure total power consumption of those 4 fans is not bigger then 1 A. Also, don't mix 3-pin and 4-pin fans on one splitter - choose either (actually best is use same model of fan). This motherboard will have no problem controlling all fans whether they are 3 or 4 pins (again, as long as you don't mix them).

Would something like this work even better?
The cables are long and it has a separate power connector.
But then in the description it says "5 x 4pin PWM" when in the pictures it looks like 4x 3 pin and a single 4 pin connector. I won't be using the single 4 pin.

Yes, it would do. And you would not need to worry about amperage limit with that solution. However, you HAVE to use the single 4-pin cable, as it is the cable that allows motherboard to control the fans - think it as master cable and other as slaves. All the cables on this splitter are for 4-pin fans, but only one one actually has 4-pins because there can only be one master cable. But you can use it for 3-pin fans too. no problem here.

 

[iddra7]

Yes, that is possible. However you need to make sure total power consumption of those 4 fans is not bigger then 1 A. Also, don't mix 3-pin and 4-pin fans on one splitter - choose either (actually best is use same model of fan). This motherboard will have no problem controlling all fans whether they are 3 or 4 pins (again, as long as you don't mix them).

Would something like this work even better?
The cables are long and it has a separate power connector.
But then in the description it says "5 x 4pin PWM" when in the pictures it looks like 4x 3 pin and a single 4 pin connector. I won't be using the single 4 pin.

Yes, it would do. And you would not need to worry about amperage limit with that solution. However, you HAVE to use the single 4-pin cable, as it is the cable that allows motherboard to control the fans - think it as master cable and other as slaves. All the cables on this splitter are for 4-pin fans, but only one one actually has 4-pins because there can only be one master cable. But you can use it for 3-pin fans too. no problem here.

Wait, so what if I buy one 4 pin fan and 3x 3 pin fans. That way I could precisely control the 4 pin fan and then the other 3 would follow it.

 

[DRagor]

Wait, so what if I buy one 4 pin fan and 3x 3 pin fans. That way I could precisely control the 4 pin fan and then the other 3 would follow it.

Nope. That's not how it works. If you would connect 4-pin fan to master cable and 3-pin fans to other cables, the result would be: 4-pin fan is controlled, but the rest runs full speed, unless you switch the header to DC control (but then 4-pin fan may suffer as some of them don't like to be DC controlled). Again, let me repeat this: if using splitter don't mix 3 and 4 pin fans.

 

[iddra7]

Wait, so what if I buy one 4 pin fan and 3x 3 pin fans. That way I could precisely control the 4 pin fan and then the other 3 would follow it.

Nope. That's not how it works. If you would connect 4-pin fan to master cable and 3-pin fans to other cables, the result would be: 4-pin fan is controlled, but the rest runs full speed, unless you switch the header to DC control (but then 4-pin fan may suffer as some of them don't like to be DC controlled). Again, let me repeat this: if using splitter don't mix 3 and 4 pin fans.

Okay, so I will connect a 3 pin fan to the master 4 pin header and the other 3 fans to the 3 pin headers. This will still allow me to control the fans from the motherboard?

 

[DRagor]

Okay, so I will connect a 3 pin fan to the master 4 pin header and the other 3 fans to the 3 pin headers. This will still allow me to control the fans from the motherboard?

Yes. The fan control will have to be set to DC on the header, but the board should do that by default. If it does not, then you'll have to do that manually in BIOS.

 

[iddra7]

Okay, so I will connect a 3 pin fan to the master 4 pin header and the other 3 fans to the 3 pin headers. This will still allow me to control the fans from the motherboard?

Yes. The fan control will have to be set to DC on the header, but the board should do that by default. If it does not, then you'll have to do that manually in BIOS.

Thank you very much.