How To Connect Case Fans To The Power Supply?


Are you looking for information on connecting the case fans to the power supply unit? Then you are at the right place. Connecting case fans to the motherboard can be tricky if you do not have the technical know-how but not after reading this article. Case fans are inevitable for the power supply unit or PSU, which gets heated up and needs something to cool down.

There are two methods to connect the case fans. Here, you can find all the steps explained clearly to make the connection successfully.

How Many Case Fans Do You Require?

The number of case fans required depends on the case. Small portable cases usually have limited space and accommodate just one fan. Suppose you install two fans to blow the hot air out. In that case, more air could go out than what comes in. You can create a balance by having one intake and one exhaust fan. This will significantly lower the temperature inside the system when compared to having no fans at all.

You can also consider having one more pair of fans to lower the temperature further. It is also good to position the fans in the right spots to efficiently lower the temperature.    

How To Choose The Best Fans?

Not all case fans will be right for your system. Choosing the best fans might need some extra thoughts on your part if you don’t have fans already with you. Remember these points when you are getting new case fans.

Inexpensive fans might make a lot of noise and have a lesser life. So do your research before you go for the purchase. Go for known brands that involve lower risks.

  • Compare the factors like noise and airflow volume and choose a fan accordingly
  • The size of the fan must be just right so as to be housed inside your case
  • Larger fans can be better as they produce lesser noise. This is because they do not have to spin as fast to result in good airflow.
  • Fans with four cables are easier to control than those with three cables. 

Connecting The Case Fans

According to the kind of motherboard your PC has, the number of case fans required can vary. There can be 1, 2, or 3 fans, and you can decide the number of fans to be connected depending on the performance and temperature of your system.

Connecting Single Case Fan

If the PSU does not have a connector called Molex connector, you will have to invest in one. Remember that the connector for the case fans is called 4-pin PWM. Given below are the steps to connect a single case fan.

  • Find out which part of the power supply unit gets more heated and finalize the spot near it to connect the case fan.
  • Note that the rear part of the fan is for the exhaust and the front or face part is the suction port. The face part of the fan must be put inside for it to be able to pull out the hot air from inside. Remember this while installing the fan.
  • There are four screw holes on the four edges of the casing of the fans. Place the fan where you have decided and tighten the screws manually.
  • A case fan comes with either one or two separate cables, one of which has three pins and is called an addressable RGB. Find out the nearest fan plug connector hub of your PSU and follow the rails on the addressable RGB pin, and plug it in this hub which is a part of the motherboard.
  • If your case fan has no 3-pin digital RGB cable, you can go to the next step. This specific cable has 3 pins. You will find more plug connector hubs at the lower part of the motherboard where a 3-pin connector can be plugged in. If there are no plugs to connect, we suggest you buy a 4-pin Molex adapter that connects four 3-pin fans.
  • Once the connection of the case fan is made, you will find many cables hanging inside the PSU. The PSU will have holes through which you can pull out these cables and hide the mess.

Connecting Multiple Case Fans

If you want to connect more than one case fan, you cannot do without a fan hub that usually has ten case fan connecting hubs. If you have a fan hub, you can connect in just three steps.

  • Connect one end of the cable to the fan hub and the other end to any fan’s connecting point on the motherboard.
  • You will find a connection point of the fan hub that is located at the opposite end where the wire from the motherboard is connected. Join the L-shaped connector of the PSU to the connection edge.
  • Your case fan needs an 8-pin connector which is found in the motherboard. But if this is missing in your motherboard, you can use a 4 pin to 8 pin connector cable. If you have the Corsair PSU, then it will already have this cable adapter which is an added benefit.
  • The red port on one end of the fan hub must be connected with at least one case fan. If this red port is left without a connection, the fan hub will not work. So remember to connect one case fan to this red port first and then connect other ports.

Q&A

Can I connect fans directly to my power supply?

There are two common ways fans connect directly to a power supply. Either using a standard 4 pin power connector from the power supply, or by using an adapter board that converts the standard power supply connector to a motherboard style pin header connector.

Do Case Fans need to connect to power supply?

Power fan is for your PSU. On some units the fan will be speed variable, this is where you plug it into your motherboard to control the speed. Go ahead and plug your fans into your motherboard, advice like that is what you see in youtube comments.

Where do I power case fans?

Power connections

Most cooling fans will connect to a PC with a standard connector of some sort. Modern systems will typically use 3-pin or 4-pin dedicated fan headers, though standard MOLEX 4-pin peripheral connectors are also used. From left to right: A 3-pin connector, a 4-pin connector and a MOLEX connector.

Can 4 pin fan connect to 3 pin motherboard?

Please Note: You can connect a 3 Pin Fan to a 3 Pin or 4 Pin header on the motherboard. The fan will function normally no matter type of fan header is used.

How do I power my computer fans externally?

Quiet PC – How To Power PC Fans From the Mains

How do I control case fan speed connected to my PSU?

You cannot change its speed if the fan is connected to a PSU (Power Supply Unit) through a Molex Fan Connector. However, if the fans are connected to the motherboard, either with 3-pin or 4-pin, these third-party applications can control the fans’ speed with a click of a button.

Are Case fans powered by the motherboard?

Do case fans connect to a motherboard or power supply? Today’s current fans generally come in a 3 or 4 pin types that plug into headers on the motherboard. The 3 pin type fan speed can be voltage-controlled by software of the motherboard.

How do I connect RGB fans to power supply?

How to connect RGB Fans & other RGB products

How do I connect case fans to my motherboard?

How Do I Connect Fans to My Motherboard? As typical motherboard fan connector is a three or four-pin connector attached to the end of a PC fan’s wire. This is attached to the three or four-pin fan header on the motherboard. There’s no trick aside from lining up the notch on the connector with the guide on the header.

Where do you connect rear case fans?

How to Install a Case Fan in your PC

Where do you connect fan hubs?

How To Install a Fan Hub + How To Install an Addressable RGB Hub

What are the 3 pins on a case fan?

A three pin connector is basically power (5/12 volt), ground, and signal. The signal wire measures how fast the fan is moving without any controls for the fan’s speed. With this type, fan speed is typically controlled by increasing or decreasing the voltage over the power wire.

What is the difference between a 3 pin and 4 pin fan?

The significant difference in practice is that 4-pin fans allow for RPM to change based on the need for cooling temperature, this reduces noise and power consumption. While 3-pin can control the voltage, but the voltage can’t turn to change the fan RPM at all and accurate as much as 4 pin fans.

Can I plug a case fan into CPU opt?

Can I Use CPU OPT for Case Fan? CPU fan header, CPU OPT, and SYS fan header, if all of them are 4 pin fan headers, the motherboard, and in turn the BIOS and the OS, can control the fans’ speed. therefore, theoretically, you can connect the case fan or one of the case fans to the CPU OPT without a problem.

What voltage are computer case fans?

The voltage a computer cooling fan receives is defined by the difference between the voltage wire (+12 V) and the ground wire (+0 V). By connecting one or both wires to a different voltage, the voltage the fan receives will be different from the default 12 V the fan was designed for.

Should I install PSU fan up or down?

It is recommended to mount the power supply with its ventilation top cover facing DOWNWARD. The fan in the power supply will take in the warm air inside the computer case, and the power supply will exhaust the air through the back.

Can you plug a fan into RGB header?

If you have an ARGB fan, you can connect the fan to the RGB header. However, the RGB header needs to be a 3-pin 5V header and not the 4-pin 12V header. If you are trying to insert a normal case fan to the RGB header, it is not recommended.

How do I connect RGB case fans to my motherboard?

Install the fans in your PC case, and screw it in the designated areas. 3. Use RGB Y-Cable to connect the fan and the motherboard. Please use RGB 4-Pin connector to an RGB header, and 4-pin fan connector to a fan header on the motherboard.

Now you know that connecting the case fans is not a big task if you have the right knowledge. Ensure that the connectors, cables, or any other parts do not obstruct the blades of the case fans. It is also a good idea to install filters to prevent dust from accumulating in your device if possible.     

Andy Avery

I really enjoy helping people with their tech problems to make life easier, ​and that’s what I’ve been doing professionally for the past decade.

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