4 Header Pins
A 4-pin header is a header that has four holes or slots corresponding to four pins on a 4-pin fan. 4-pin headers are usually marked with CPU_FAN, CPU_OPT, or PWM_FAN labels on the motherboard. 4-pin header supports PWM control to adjust fan speed.
To connect a 4-pin fan with a 4-pin header, you only need to connect the fan connector with the header, ensuring that pins 1, 2, 3, and 4 on the fan match holes 1, 2, 3, and 4 on the header. You also need to pay attention to the direction of the fan cable, so as not to interfere with other components or block the flow of air.
Can I Connect a 3 3-pin fan with a 4 4-pin header or Vice versa?
The answer is yes, but there are a few things to note. 3-pin and 4-pin fans have cross-compatibility, which means they can be connected with headers with different pin counts. However, this will affect the type of control that the motherboard can exercise over fan speed.
3 Pin Fan with 4 Header Pins
If you connect a 3-pin fan with 4 header pins, you need to ensure that pins 1, 2, and 3 on the fan match holes 1, 2, and 3 on the header. Hole 4 of the header will be empty because the 3-pin fan does not have pin 4.
Thus, you cannot use PWM control to adjust the fan speed, but can only use voltage control. However, not all motherboards support voltage control for the 4-pin header, so you need to check your motherboard’s specifications first.
4 Pin Fan with 3 Header Pins
If you connect a 4-pin fan with 3 header pins, you need to make sure that pins 1, 2, and 3 on the fan match holes 1, 2, and 3 on the header. Pin 4 on the fan will hang because the 3 header pins do not have 4 holes.
Thus, you cannot use PWM control to adjust the fan speed, but can only use voltage control. However, this method is not optimal, because the 4-pin fan is designed to use PWM control, so you may encounter problems such as noisy, unstable, or malfunctioning fans.
Conclusion
3-pin and 4-pin fans are fans that have differences in terms of the number of pins, functions, features, and how to install them. The 3-pin fan has a fixed speed, which can be adjusted with voltage control. The 4-pin fan has a dynamic speed, which can be adjusted with PWM control. 3-pin and 4-pin fans can be connected to different headers by different pin counts, but this will affect the type of control that the motherboard can perform.
Hopefully, this article is useful for those of you who want to know what is the difference between a 3-pin and 4-pin fan for a CPU, as well as how to connect it to the motherboard. Thank you for reading this article, and see you in the next article.