Need help with fan setup

[Cj-Puerto]

Hello to everyone,i would like if someone could shine a light on how to setup my pc case fans with the current stuff i have. 

 

Right now i have:

1 - 120mm airflow fan, 1200rpm (3pin) (stock case fan, dont know the powerdraw from this one)

2 - 120mm airflow fans, 1200 rpm (4pin) (0.15 + 10%A or 12V (this is what the box says, i dont really understand much about power draw)

1 - 140mm high static pressure fan, 1700 rpm (4pin) (0.12amp)

Sock AMD cpu cooler (Ryzen 5 3400g) (i dont know the power draw for this one)

1 - fan hub with molex power connection and connection to the motherboard for fan controll (compatible with 3 and 4 pin fans)

1 - 3 headed fan splitter  (compatible with 3 and 4 pin fans) 

 

My motherboard only has 2 fan pin headers. (Up to 2 amps) (Gibagyte b450 Ds3h) 

 

As of right now i have all the 120mm connected to the fan hub, and they are running at full speed since the fan hub is only connected to the psu.

 

Both the Cpu fan and the 140mm fan are connected to the mother board in order to controll their speed. 

 

I havent connected all of my case fans to the hub since i have read that connecting fans with different amperage, rpm and number of pins might cause some trouble.

 

Can anyone help me think of a setup with the components i have? i would like to be able to controll all of my fans and i dont want to fry my motherboards pin headers. 

 

Recommendations on changing the setup by buying more stuff is also appreciated.

 

Thanks 

 

[Guest]

Find a nice fan controller. 

[DragonTamer1]

Does your fan hub have a cable to connect it to the motherboard for control?

What case do you have?

[Cj-Puerto]

14 hours ago, DragonTamer1 said:

Does your fan hub have a cable to connect it to the motherboard for control?

What case do you have?

Hello, ty for your reply. 

Yes, the fan hub does have a cable to connect it to the mobo.

 

Im using a Coolermaster Q300l Case, having mixed feelings about it tho. 

 

 

[DragonTamer1]

The Q300l is  not well ventilated at the bottom of the case for the GPU. If you have a GPU I would recommend turning your power supply upside down or removing some of the remaining PCIe brackets so air can get in/out around the GPU.

 

This case will benefit most from having a negative pressure setup so I would take the stock case fan and run it at full speed (provided it's not too loud for you) by plugging it into your fan up without any control. This fan most likely can't be controlled in this current setup is unless you are willing to do some electrical engineering work.

 

I would take your two airflow fans and mount them on the front of the case for intake but you would fair better with static pressure fans instead. You can take the 140mm and mount it on the top of your case as an exhaust at the back. Tie these three fans together with the fan splitter cable on your open fan header.

 

Ideally you should have two high static pressure fans on the front as intake tied to the fan header on your board with at least one PWM exhaust fan tied to the speed of your CPU (shares the CPU fan header) at the back and top rear of the case.

[Cj-Puerto]

3 hours ago, DragonTamer1 said:

The Q300l is  not well ventilated at the bottom of the case for the GPU. If you have a GPU I would recommend turning your power supply upside down or removing some of the remaining PCIe brackets so air can get in/out around the GPU.

 

This case will benefit most from having a negative pressure setup so I would take the stock case fan and run it at full speed (provided it's not too loud for you) by plugging it into your fan up without any control. This fan most likely can't be controlled in this current setup is unless you are willing to do some electrical engineering work.

 

I would take your two airflow fans and mount them on the front of the case for intake but you would fair better with static pressure fans instead. You can take the 140mm and mount it on the top of your case as an exhaust at the back. Tie these three fans together with the fan splitter cable on your open fan header.

 

Ideally you should have two high static pressure fans on the front as intake tied to the fan header on your board with at least one PWM exhaust fan tied to the speed of your CPU (shares the CPU fan header) at the back and top rear of the case.

Yes, indeed, the case is not too good for GPU temps. 

 

I'll give your suggestions a shot and see how it goes. 

 

Thank you

[WoodenMarker]

On 9/19/2020 at 8:49 AM, Cj-Puerto said:

2 - 120mm airflow fans, 1200 rpm (4pin) (0.15 + 10%A or 12V (this is what the box says, i dont really understand much about power draw)

I havent connected all of my case fans to the hub since i have read that connecting fans with different amperage, rpm and number of pins might cause some trouble.

12v is standard for pc fans. The motherboard supporting up to 2A means that you can have up to that combined value which would support ~13 fans that each require 0.15A. The ±10% is deviation from 0.15A to account for differences from manufacturing. 

Connecting fans with different amperage is fine as long as it doesn't require more amperage than the header can support. Different rpm isn't an issue unless you want to control fans in a specific way.

Using fans with different numbers of pins is fine as long as you understand what the pins are for and what is needed for fan control. 

A fan splitter / hub will generally read the rpm from one fan. Sometimes, that means that the 3rd pin is missing from every header that isn't the master and sometimes the 3rd pin is present but just a dummy / unused pin. 

Mixing 3 and 4pin fans is mainly an issue when a pwm signal is used. The pwm ic on a 4pin fan modulates the incoming 12v to control fan speed. A 3pin fan lacks that pin / function and will just receive 12v to run at 100% rpm. For control when mixing 3 / 4pin fans, use dc instead of pwm. This ignores the pwm function completely though so the rpm control won't be as granular. 

 

It's recommended to split 3pin and 4pin fans into separate groups for finer control. 

What hub are you using? 

[Cj-Puerto]

2 hours ago, WoodenMarker said:

12v is standard for pc fans. The motherboard supporting up to 2A means that you can have up to that combined value which would support ~13 fans that each require 0.15A. The ±10% is deviation from 0.15A to account for differences from manufacturing. 

Connecting fans with different amperage is fine as long as it doesn't require more amperage than the header can support. Different rpm isn't an issue unless you want to control fans in a specific way.

Using fans with different numbers of pins is fine as long as you understand what the pins are for and what is needed for fan control. 

A fan splitter / hub will generally read the rpm from one fan. Sometimes, that means that the 3rd pin is missing from every header that isn't the master and sometimes the 3rd pin is present but just a dummy / unused pin. 

Mixing 3 and 4pin fans is mainly an issue when a pwm signal is used. The pwm ic on a 4pin fan modulates the incoming 12v to control fan speed. A 3pin fan lacks that pin / function and will just receive 12v to run at 100% rpm. For control when mixing 3 / 4pin fans, use dc instead of pwm. This ignores the pwm function completely though so the rpm control won't be as granular. 

 

It's recommended to split 3pin and 4pin fans into separate groups for finer control. 

What hub are you using? 

Hello, thank you for your reply.

 

So, in theory, i should be fine if i connect all my fans to my hub, as long as i dont use the pwm signal to controll them?

 

Should i just get another 4 pinned, preferably a high static pressure, fan to use the pwm signal with my hub and replace the stock case fan?

 

As of right now, im using a fan hub similar to this one

 

https://www.amazon.com/Cable-divisor-ventilador-amarillo-unidades/dp/B08337VNG3/ref=sr_1_2_sspa?__mk_es_US=ÅMÅŽÕÑ&dchild=1&keywords=fan+hub&qid=1600649140&sr=8-2-spons&psc=1&spLa=ZW5jcnlwdGVkUXVhbGlmaWVyPUEyR0w3N1FVODFGRFBGJmVuY3J5cHRlZElkPUEwNTA1NjQyMUNBM0M2MTYwSDdRRiZlbmNyeXB0ZWRBZElkPUEwMTMwMDEwTUYyUFNIV1NGNzRMJndpZGdldE5hbWU9c3BfYXRmJmFjdGlvbj1jbGlja1JlZGlyZWN0JmRvTm90TG9nQ2xpY2s9dHJ1ZQ==

 

Thank you for your help.

 

 

[WoodenMarker]

19 hours ago, Cj-Puerto said:

So, in theory, i should be fine if i connect all my fans to my hub, as long as i dont use the pwm signal to controll them?

 

Should i just get another 4 pinned, preferably a high static pressure, fan to use the pwm signal with my hub and replace the stock case fan?

 

As of right now, im using a fan hub similar to this one

https://www.amazon.com/Cable-divisor-ventilador-amarillo-unidades/dp/B08337VNG3/

A powered pwm hub sends a pwm signal to all fans so just plug your 4pin pwm fans to it. 3pin fans would just run at 100% rpm if connected to such a hub. If you're satisfied with your current 3pin fans, I recommend powering them off of a normal fan splitter connected to a motherboard fan header and controlling them from there. 

[Cj-Puerto]

1 hour ago, WoodenMarker said:

A powered pwm hub sends a pwm signal to all fans so just plug your 4pin pwm fans to it. 3pin fans would just run at 100% rpm if connected to such a hub. If you're satisfied with your current 3pin fans, I recommend powering them off of a normal fan splitter connected to a motherboard fan header and controlling them from there. 

Cool, ty for your reply. 

 

So i'm good if i connect all my fans to my hub while using the pwm signal from the mobo? only thing would be that the 3 pin fan would run at full speed all time?

 

Thanks for your help

[WoodenMarker]

7 hours ago, Cj-Puerto said:

So i'm good if i connect all my fans to my hub while using the pwm signal from the mobo? only thing would be that the 3 pin fan would run at full speed all time?

Yes, you can do that. Most people would want to run fans at lower rpm when not necessary to minimize noise.