3 Pin Vs 4 Pin Fans Connector For CPU, Which One To Have On Header?

If you’re grappling with the decision of whether to choose a 3 pin or a 4 pin fan for your computer setup, be prepared to encounter a wealth of conflicting information. While from an external perspective, there may not appear to be significant differences between the two types of fans, there are subtle yet critical factors to consider once you delve into the inner workings of these components.

3 Pin vs 4 Pin Fan

In this guide, our knowledgeable experts will help you navigate the complex world of computer fans, elucidating the significance of voltages, and providing a detailed analysis of whether a 4 pin CPU fan or a 3 pin fan would be the better choice for your specific needs. It is important to thoroughly read the entirety of this guide and thoughtfully consider how you utilize your computer, as this will play a crucial role in determining your ultimate decision.

3 Pin vs 4 Pin Fan


Let’s dive deeper into the topic and explore the nuances of 3 pin and 4 pin fan connectors.

3 Pin Fan

First, a 3 pin fan gets its name from the fact that it has three pins or indicators, which correspond to three wires – one for power, one for ground, and one for tachometric signal or speeds. These wires work in tandem to regulate fan speed, performance, and PC cooling. The tachometric signal plays a key role in controlling the 3 pin fan’s behavior, adjusting the amount of power applied to the motor by transmitting the fan impeller’s speed (i.e., the fan’s rotation) at a predetermined voltage, typically ranging from 5 to 12 volts in most standard fans.

When the fan’s voltage increases or decreases, its speed changes as well. Other than that, a 3 pin fan functions similarly to any other type of computer fan by moving hot air from various components (such as the motherboard or CPU) and expelling it through vents.

4 Pin Fan

In contrast, modern computer builds and motherboards have shifted away from 3 pin fans and toward 4 pin fan headers. A 4 pin fan connector is distinct from a 3 pin fan connector due to its fourth wire – the “PWM wire” or Pulse Width Modulation wire. This wire is crucial in controlling the power supply of the load, which in turn regulates the rotation speed of the fan impeller.

3 Pin vs 4 Pin Fan


PWM (Pulse Width Modulation)

The PWM wire plays a pivotal role in most contemporary gaming setups and professional computers, adjusting the speed and providing feedback to minimize noise and optimize cooling efficiency. This single wire is the primary distinguishing factor between 4 pin and 3 pin fans, although there are other differences to be aware of that set them apart.

The table below summarizes the key differences between 3 pin and 4 pin fans:

  • Features 3 Pin Fan / 4 Pin Fan
  • Pulse Width Modulation Not automatic / Automatic
  • Noise Control Steady and consistent noise / Quiet most of the time
  • Compatibility Better with smaller fans / Used with parts that have high power consumption
  • Longevity Shorter lifespan / Longer lifespan

While 4 pin fans tend to be quieter, last longer, and have automatic Pulse Width Modulation, 3 pin fans tend to be noisier, have a shorter lifespan, and their rotation speed is controlled through software. It is important to keep in mind that there are other differences to consider, which impact how the fans themselves operate and interact with the rest of the computer, rather than just how they physically cool it.

3 Pin vs 4 Pin Fan Connector: Which Should I Get?

Choosing between a 3 pin and 4 pin fan may seem like a small decision, but it can have a significant impact on the overall performance of your computer. By understanding the technical differences and weighing the advantages and disadvantages of each type of fan, you can make an informed decision that best suits your specific needs and preferences.


The importance of pulse width modulation (PWM) and the differences between 3 pin and 4 pin fans have become increasingly relevant in the world of computer technology. PWM is crucial for maintaining optimal cooling and controlling heat when a processor is under heavy load, and it is one of the main reasons why 4 pin fan headers are now so compatible with modern computer parts, including video cards.

Do 3 pin fans do not have control over speed and voltage?

While it is possible for a 3 pin fan connector to control rotational speed, it is more difficult and requires software to be done manually, making it less efficient than the automatic control of voltage and speed offered by PWM. The noise control differences between 3 pin and 4 pin fans are also noteworthy. 3 pin fans rotate at high potential, generating a steady and consistent noise, while 4 pin fans are quieter overall but have less consistent sound, which may be more distracting to some people.

Can I plug 3 pin fans into 4 pin fan header, will it work?

When it comes to compatibility with other parts, CPU fans must be compatible with other components in a build. 3 pin connectors are better suited to smaller fans that do not require a lot of power, while 4 pin fan connectors are used with high power consumption parts. Additionally, longevity is a significant factor to consider. Since most modern fans use 4 pins, they tend to have a longer lifespan because of the variations in speed.

3 Pin vs 4 Pin Fan

In conclusion, if you are in the market for a new fan for your computer, investing in a 4 pin fan with PWM technology is your best bet. This type of fan is future-proof and provides better cooling, ultimately protecting your other investments. While a 3 pin fan may be suitable for word processing or social media tasks, gamers and editors should opt for a 4 pin fan to get the full benefits of PWM and ensure their computer stays cool and long-lasting.

Leave a Comment