Common power interface types
Common power interface types for Chassis Fans are mainly 3-pin and 4-pin. The 3-pin interface contains the positive and negative poles of the power supply and the speed measurement line. It can provide basic power supply for the fan and allow the motherboard to read the fan speed information through the speed measurement line. This interface is more common in some basic Chassis Fans. It has wide compatibility and can adapt to the fan interface of most motherboards. The 4-pin interface has an additional speed adjustment line based on the 3-pin, also known as the PWM interface. It can achieve more precise fan speed adjustment. According to the motherboard BIOS settings or software control, it can automatically adjust the fan speed under different loads to balance the heat dissipation effect and noise level.
Compatibility with the motherboard
In terms of compatibility with the motherboard, the 3-pin interface fan can be connected to the 3-pin or 4-pin fan interface on the motherboard. When connected to the 4-pin interface, only the positive and negative poles of the power supply and the speed measurement line function are used, and PWM speed regulation cannot be achieved, but it can operate normally and feedback speed information. The 4-pin PWM interface fan is best connected to the 4-pin PWM interface of the motherboard to give full play to its intelligent speed regulation function. However, some older motherboards may not have a 4-pin PWM interface. In this case, a 4-pin fan can also be connected to a 3-pin interface, but it can only run at a fixed speed. Most new motherboards are equipped with a variety of 3-pin and 4-pin interfaces, which are well compatible with various chassis fans, providing users with multiple choices and flexible fan speed control solutions.
Direct connection to power supply
In addition to connecting to the motherboard, the chassis fan can also be directly connected to the power supply. Some chassis fans are equipped with a large 4-pin Molex interface, which can be directly connected to the large 4-pin output interface of the power supply to obtain power. This connection method does not rely on the motherboard and is suitable for some situations where the number of motherboard fan interfaces is insufficient or the fan power supply needs to be independently controlled. For example, when some server chassis or DIY players make special layouts and controls for the chassis fan, directly taking power from the power supply can easily realize the independent switch and speed regulation of the fan, which is not limited by the motherboard BIOS settings. However, this connection method cannot achieve accurate monitoring and intelligent control of the fan speed by the motherboard, and the fan speed needs to be adjusted manually or an additional speed regulator is used.
Compatibility Summary and Expansion
Chassis Fan has various types of power interfaces. When choosing and using them, you need to consider their compatibility with the motherboard and power supply. For ordinary users building desktops, the fan interface on the motherboard can basically meet the connection requirements of common chassis fans. Giving priority to fans that match the motherboard interface can make full use of the motherboard's speed regulation and monitoring functions. For users with special needs, such as chassis modification enthusiasts or server builders, understanding the different power interfaces of the fan and how it is directly connected to the power supply can better implement personalized chassis cooling solutions and improve the stability and service life of the internal components of the chassis. At the same time, it can also flexibly adjust the operating status of the fan according to actual needs and find the best balance between cooling effect and noise control.
