A CHA fan on a motherboard refers to a fan header or connector designed to connect and control additional chassis fans. The CHA acronym " Chassis " indicates that the fan header is intended for use with case fans rather than CPU or GPU fans.

Most modern motherboards come with multiple CHA fan headers, which allow users to connect multiple case fans to the motherboard and control their speed and operation through the BIOS or UEFI firmware or through specialized software such as the manufacturer’s proprietary fan control utility.

The ability to monitor and control the speed of case fans is important as it helps regulate the temperature inside the computer case, which can help improve the longevity and performance of other components such as the CPU, GPU, and hard drives.

Key Takeaways

  • A “chassis fan,” or CHA, is a fan header on a motherboard that connects to and powers additional fans inside the computer’s chassis. 
  • A fan header connects the CHA fan to the motherboard, allowing the motherboard to regulate the fan’s speed and track its temperature. Based on the temperature of the internal components of the case, the motherboard may modify the fan’s speed.
  • The main and 4-pin power supplies are connected to the CHA Fan on the motherboard, using either an internal or external connection to attach the 4-pin power supply to the fan headers.

What Functions Does A CHA Fan Perform? 

A CHA fan, or chassis fan, is a component that helps cool a computer case’s interior. It does this by circulating air to dissipate heat generated by the various components inside the case. The CHA fan is typically connected to the motherboard through a fan header, allowing it to control the fan’s speed and monitor its temperature. 

In most cases, there are some manual ways that can be used to adjust the fan’s speed based on the temperature of the components inside the case. Anyhow, there are several benefits of having CHA fans on the motherboard. A few of the advantages of having a CHA fan on the motherboard are included as follows: 

  • A CHA fan’s key role is to circulate air to cool a computer case’s inner while dissipating heat from external components.

  • A properly performing CHA fan may assist in maintaining the internal components' temperature within acceptable operating ranges, preventing overheating and extending the life of the parts.

  • The motherboard may boost the fan speed to pull more cold air into the case and push more hot air out when the internal temperature is high. The internal temperature can be lowered. As a result, keeping the components cold.

  • A well-working CHA fan may help reduce computer noise levels and cool the interior components. The fan will be quiet while operating at a low speed compared to a high one.

How To Connect and Setup CHA Fan? 

The CHA fan header is normally found next to the edge of the motherboard, close to the front or back of the chassis, and is commonly labeled “CHA FAN” or “CHASSIS FAN”. To connect and set up a CHA fan on a motherboard, follow these steps:

Step 1: Locate CHA Fan Header

Most motherboards have multiple CHA fan headers labeled “CHA_FAN1,” “CHA_FAN2,” etc. Refer to your motherboard’s user manual to locate the header.

The fan header normally has three or four pins and could contain a little plastic tab or lever to secure the connector.

Step 2: Connect the Fan to CHA Fan Header.

Connect the fan’s 3-pin or 4-pin connector to the CHA fan header on the motherboard. Make sure the connection is secure and aligned correctly.

By carefully putting the fan cable into the CHA fan header while lining up the cable’s pins with the header, you may connect the fan. Ensure the plastic tab or lever holding the connector is attached tightly.

Step 3: Power on Computer.

Ensure the CHA fan is running as soon as the computer starts. Utilize the BIOS or system monitoring software to check the fan speed and temperature.

Step 4: Configure Fan Settings in BIOS/UEFI Firmware.

To configure fan settings in BIOS/UEFI firmware, enter the BIOS/UEFI firmware by pressing the designated key during system boot (usually F2, F10, or Delete).

Navigate to the fan settings section, and set the fan’s control mode (e.g., PWM or DC) and target speed. You may also set temperature thresholds that trigger the fan to speed up or slow down.

Step 5: Install Fan Control Software (optional).

Some motherboard manufacturers provide fan control software allowing users to fine-tune the operating system’s fan settings. Install the software and adjust fan settings as desired.

Step 6: Check the Temperature. 

Once the fan is connected and configured, test it by running intensive tasks that generate heat, such as gaming or rendering.

Verify the internal temperature is kept within the safe working ranges and that the fan is functioning at the proper speed to keep the components cool.

Use monitoring software to check the fan’s speed and temperature and adjust the settings to maintain optimal performance and noise levels.

Connections and Power Source

A CHA Fan on a motherboard is connected to two power sources: the main and the 4-pin power supply. The main power supply provides the power needed to run the fan, while the 4-pin power supply controls the fan speed.

The 4-pin power supply is connected to the motherboard’s fan headers through an Internal or external connection. The fan headers provide the voltage, ground, and control signals to the fan to regulate its speed. This can be done through manual controls or software, depending on the motherboard and fan system.

It is important to make sure that the correct connection is used for each fan and that the power source for the fan is the appropriate voltage. Additionally, it is important to ensure that the 4-pin power supply is properly connected to the right fan header on the motherboard to ensure accurate control.

Zohaib Hassan Bhatti
Zohaib Hassan is a staunch tech enthusiast and has been writing about his interactions with computers for years. He has been serving the PCIdeaz as a content manager along with experimenting and testing numerous tech masterpieces. Indeed, he often forgets about eating his spicy snacks when has his head on the computer screen.