[SOLVED] Should i connect 3 fans to one chassis fan header?

Jan 14, 2021
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i'm using a H110M-F MOBO and i want to put 3 fans on it..so is it ok for me to connect 3 fans to a single chassis fan header, should i use a splitter or a hub that connects to my psu? sorry i'm new to this pc building stuffs
 
Solution
You have most of the info, but need more. There is only one CHA_FAN 4-pin header near mid-board, and it can only use the new PWM Mode for fan speed control. Thus you MUST buy the newer 4-pin PWM type fans - no 3-pin fans.

Next, fan lights. NONE for your purpose. The CHA_FAN header you need to use for your CASE ventilation fans can supply up to 1.0 A max current to the total load connected to it. Almost all common normal fans today pull from 0.1 to 0.25 A max, so three fans can be done on one header. IF you plan more than that, you need to find out for sure the max current spec for them and add them up - do not exceed 1 A.

The earliest fan type that had lights in them are called LED fans. They have only one cable in them, just like any...

Ralston18

Titan
Moderator
Immediate answer - no.

Do not do anything without reading through all of the build's component documentation.

Motherboard, CPU, GPU, case, fans,PSU, etc...

What power supply do you have? Make, model, wattage, age, condition?

Update your post to include full system hardware specs and OS information.

The motherboard's User Manual is the key document. However the User Manual often refers back to the manufacturer's website for more more detailed information including updates and changes. There are often quite a number of notes and warnings that must be read.

Start with the following link.

https://dlcdnets.asus.com/pub/ASUS/mb/LGA1151/H110M-K/G10950_H110M-K_UM_WEB_only.pdf

Do verify that I correctly identified the applicable User Manual

Plan out your build and its' assembly: step by step and confirm that you can indeed "put 3 fans on it". That may not even be necessary - have functional, performance reasons for doing things.

Not cosmetics - e.g., "pretty lights" (my quotes).
 
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hi, most fan headers are rated for 1 Amper,
look at sticker on your fans, it should tell you how much ampers it eats.
if fans are 0.3A each or less, u can use 3 fan Y splitter (cheapest option).
if they have more, u have to add some extra ampers, coz when fan motor start up it can push more amps then it says on sticker, so in this case, ull need powered (sata/molex) fan hub, preferably mainboard controlled (so u can tune fan speeds based on pc temps)

if u choose fan hub, see your power supply if u have free sata or molex connector, to avoid some hassle, then purchase one for free sata/molex port u got

for both splitter/fan hub, make sure they are PWM, as your mainboard supports it.
if u have mixed PWM/DC fans (3pin/4pin) u will need to run them in DC mode (bios setting) as PWM will not work with DC fans, while DC will work with PWM

a side note, your board has written Fan Xpert while hawing just 1 fan connector hehe, kinda ironic xD
 
  • Like
Reactions: Dan Ridge
Jan 14, 2021
5
0
10
Immediate answer - no.

Do not do anything without reading through all of the build's component documentation.

Motherboard, CPU, GPU, case, fans,PSU, etc...

What power supply do you have? Make, model, wattage, age, condition?

Update your post to include full system hardware specs and OS information.

The motherboard's User Manual is the key document. However the User Manual often refers back to the manufacturer's website for more more detailed information including updates and changes. There are often quite a number of notes and warnings that must be read.

Start with the following link.

https://dlcdnets.asus.com/pub/ASUS/mb/LGA1151/H110M-K/G10950_H110M-K_UM_WEB_only.pdf

Do verify that I correctly identified the applicable User Manual

Plan out your build and its' assembly: step by step and confirm that you can indeed "put 3 fans on it". That may not even be necessary - have functional, performance reasons for doing things.

Not cosmetics - e.g., "pretty lights" (my quotes).
ok noted sir, thank you
 
Jan 14, 2021
5
0
10
hi, most fan headers are rated for 1 Amper,
look at sticker on your fans, it should tell you how much ampers it eats.
if fans are 0.3A each or less, u can use 3 fan Y splitter (cheapest option).
if they have more, u have to add some extra ampers, coz when fan motor start up it can push more amps then it says on sticker, so in this case, ull need powered (sata/molex) fan hub, preferably mainboard controlled (so u can tune fan speeds based on pc temps)

if u choose fan hub, see your power supply if u have free sata or molex connector, to avoid some hassle, then purchase one for free sata/molex port u got

for both splitter/fan hub, make sure they are PWM, as your mainboard supports it.
if u have mixed PWM/DC fans (3pin/4pin) u will need to run them in DC mode (bios setting) as PWM will not work with DC fans, while DC will work with PWM

a side note, your board has written Fan Xpert while hawing just 1 fan connector hehe, kinda ironic xD
yes it has 4-pin/3-pin PWM/DC mode for case fans
a simple BIOS adjustment lets you run your case fan in PWM/DC. Fan Xpert even includes Auto-Tuning mode to scan and detect all fan characteristics for single-click customization! this is what is says, it says it has a maximum of 1A (12w) fan power, it has 2 fan headers, 1 for CPU HS and then the Chassis fan. i have a True Rated deepcool imaster 500w PSU. so i think its possible to use both of your suggestions sir... thanks for your input sir i'll keep it in mind
 

Paperdoc

Polypheme
Ambassador
You have most of the info, but need more. There is only one CHA_FAN 4-pin header near mid-board, and it can only use the new PWM Mode for fan speed control. Thus you MUST buy the newer 4-pin PWM type fans - no 3-pin fans.

Next, fan lights. NONE for your purpose. The CHA_FAN header you need to use for your CASE ventilation fans can supply up to 1.0 A max current to the total load connected to it. Almost all common normal fans today pull from 0.1 to 0.25 A max, so three fans can be done on one header. IF you plan more than that, you need to find out for sure the max current spec for them and add them up - do not exceed 1 A.

The earliest fan type that had lights in them are called LED fans. They have only one cable in them, just like any simpler fan, and some LED'[s in the frame of one colour. These are simply connected in parallel with the fan motor, so they add to the current max spec. Such fans have max's of 0.2 to 0.45 A, so you must be very careful about connecting several to one header.

The popular current RGB and ADDR RGB fans with multi-colur lights in their frames that generate changing displays do not have those current limits because the LED's in them are supplied separately with their own power cable from a different mobo header that provides power and display control. However, your mobo does not have any such lighting header, so to use such a fan type you would need to get a suitable third-parry lighting controller, too.
 
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Reactions: Dan Ridge
Solution
Jan 14, 2021
5
0
10
You have most of the info, but need more. There is only one CHA_FAN 4-pin header near mid-board, and it can only use the new PWM Mode for fan speed control. Thus you MUST buy the newer 4-pin PWM type fans - no 3-pin fans.

Next, fan lights. NONE for your purpose. The CHA_FAN header you need to use for your CASE ventilation fans can supply up to 1.0 A max current to the total load connected to it. Almost all common normal fans today pull from 0.1 to 0.25 A max, so three fans can be done on one header. IF you plan more than that, you need to find out for sure the max current spec for them and add them up - do not exceed 1 A.

The earliest fan type that had lights in them are called LED fans. They have only one cable in them, just like any simpler fan, and some LED'[s in the frame of one colour. These are simply connected in parallel with the fan motor, so they add to the current max spec. Such fans have max's of 0.2 to 0.45 A, so you must be very careful about connecting several to one header.

The popular current RGB and ADDR RGB fans with multi-colur lights in their frames that generate changing displays do not have those current limits because the LED's in them are supplied separately with their own power cable from a different mobo header that provides power and display control. However, your mobo does not have any such lighting header, so to use such a fan type you would need to get a suitable third-parry lighting controller, too.
i actually dont care about RGB lightings i just want my unit to have a better ventilation. my case can only hold 2 add fans so i'm just gonna buy only 2 PWM (4pins) fans, if i may ask, what type of fans should i buy that has a low power consumption? your opinions would help alot for me. thank you !
 

Paperdoc

Polypheme
Ambassador
OK, fans with no lights makes it easier. Personally I have always liked Notcua fans, and they make many models with no lights. Their fans have a reputation for long life (6 year warranty, and normally last much longer), quite operation, and good airflow. Some find their prices a bit too high, and some do not like their common 2-tone brown colour scheme, although they also have greys. My son gave me the machine I'm using now equipped with beQuiet Pure Wings 2 fans, and they are very quiet and do a good job.

You are looking for case ventilation fans, so you do not need the ones rated for "high pressure". Those are designed to push good airflow though some backpressure due to air flow resistance, such as through a radiator or the fins of a heatsink on a CPU. But fans optimized for less backpressure can deliver more airflow in those conditions. In this context we look at the "pressure" specs expressed in mm of water, and values below 1.5 are quite all right for case fans. The most important specs for such fans are the max air flow (usually in CFM, sometimes in m³/hr), the max current in A, and the max noise in dBA. In your case, look only at 4-pin PWM fans, not 3-pin ones.

For the Noctua line, start here

https://noctua.at/en/products/fan

They are organized by size, and I expect you want 120mm. The first group are all their recent models with the two-tone brown colours. Ignore the second group of black ones from their IndustrialPPC line - they are powerful and you don't need them. The third group are grey ones in the redux line - just a slightly older design, but very good still and slightly lower priced. Next note the last column of each table - it details whether this is a PWM model. Note in the first column that some models are designed to 5 V operation - do NOT get one of those. Noctua specs air flow in m³/hr whereas most N.A. companies use CFM. The conversion factor is 0.5886, so 100 m³/hr = 58.86 CFM.

In the first group, the model NF-S12A PWM has the highest airflow for a 4-pin fan, low noise, and acceptable pressure. Click on the model name in the first column to get more complete info, and you see in its specs that is max current pull is 0.12 A. You can look at others in the main product list and choose. For example, further down in the redux line the model NF-P12 redux -1700PWM has even higher airflow with more noise generation and higher pressure, and a max current of 0.09 A.

Noctua ships many of their fans with accessories called LNA's (Low Noise Adapters) that are little things you can insert into the power connectors where they plug into the fan header. They are useful ONLY when you connect your fan to an uncontrolled power source (such as directly from a PSU) and want to permanently reduce their speed, airflow and noise. When using the fan with an automatic fan speed control system such as your mobo header provides, do NOT use this accessory - it only interferes with the fan control and limits its maximum use when your workload is high.

The fans I have in this machine are the beQuiet Pure Wings 2 120mm PWM model here

https://www.bequiet.com/en/casefans/617

Specs are max 1500 RPM, airflow 87 m³/hr (51.4 CFM), pressure 1.25 mm water and noise 20.2 dBA. They don't have the higher max airflow of the Noctuas above, but they do very well for my uses and are running well below max speed so their noise is really almost none. No max current spec, but I'm sure it is no more than 0.15 A per fan.
 
Last edited:
  • Like
Reactions: Dan Ridge
Jan 14, 2021
5
0
10
OK, fans with no lights makes it easier. Personally I have always liked Notcua fans, and they make many models with no lights. Their fans have a reputation for long life (6 year warranty, and normally last much longer), quite operation, and good airflow. Some find their prices a bit too high, and some do not like their common 2-tone brown colour scheme, although they also have greys. My son gave me the machine I'm using now equipped with beQuiet Pure Wings 2 fans, and they are very quiet and do a good job.

You are looking for case ventilation fans, so you do not need the ones rated for "high pressure". Those are designed to push good airflow though some backpressure due to air flow resistance, such as through a radiator or the fins of a heatsink on a CPU. But fans optimized for less backpressure can deliver more airflow in those conditions. In this context we look at the "pressure" specs expressed in mm of water, and values below 1.5 are quite all right for case fans. The most important specs for such fans are the max air flow (usually in CFM, sometimes in m³/hr), the max current in A, and the max noise in dBA. In your case, look only at 4-pin PWM fans, not 3-pin ones.

For the Noctua line, start here

https://noctua.at/en/products/fan

They are organized by size, and I expect you want 120mm. The first group are all their recent models with the two-tone brown colours. Ignore the second group of black ones from their IndustrialPPC line - they are powerful and you don't need them. The third group are grey ones in the redux line - just a slightly older design, but very good still and slightly lower priced. Next note the last column of each table - it details whether this is a PWM model. Note in the first column that some models are designed to 5 V operation - do NOT get one of those. Noctua specs air flow in m³/hr whereas most N.A. companies use CFM. The conversion factor is 0.5886, so 100 m³/hr = 58.86 CFM.

In the first group, the model NF-S12A PWM has the highest airflow for a 4-pin fan, low noise, and acceptable pressure. Click on the model name in the first column to get more complete info, and you see in its specs that is max current pull is 0.12 A. You can look at others in the main product list and choose. For example, further down in the redux line the model NF-P12 redux -1700PWM has even higher airflow with more noise generation and higher pressure, and a max current of 0.09 A.

Noctua ships many of their fans with accessories called LNA's (Low Noise Adapters) that are little things you can insert into the power connectors where they plug into the fan header. They are useful ONLY when you connect your fan to an uncontrolled power source (such as directly from a PSU) and want to permanently reduce their speed, airflow and noise. When using the fan with an automatic fan speed control system such as your mobo header provides, do NOT use this accessory - it only interferes with the fan control and limits its maximum use when your workload is high.

The fans I have in this machine are the beQuiet Pure Wings 2 120mm PWM model here

https://www.bequiet.com/en/casefans/617

Specs are max 1500 RPM, airflow 87 m³/hr (51.4 CFM), pressure 1.25 mm water and noise 20.2 dBA. They don't have the higher max airflow of the Noctuas above, but they do very well for my uses and are running well below max speed so their noise is really almost none. No max current spec, but I'm sure it is no more than 0.15 A per fan.
thank you very much sir, i'll look into what you've suggested