The Basics of Fanless Cooling Technology

Find all of the essential information you need on fanless cooling technology.

When a computer is operating, heat is generated as a byproduct of the computer’s components. While these components are designed to produce as little heat as possible, excess heat can still accumulate. If the components overheat, they can malfunction, become damaged, and force the computer to shut down. Therefore, problems will arise when the amount of heat being removed cannot overcome the amount of heat produced. To keep the components cool, fans are typically used to expel the heat. However, fanless technology such as DNP's Vapor Chamber is a new and improved method that removes heat passively. Here we will highlight the main features of fanless technology and how it is used.

Fanless Cooling Technology

See 11 related fields


What is "Fanless Cooling Technology"?

Fans are required when natural heat loss is insufficient to overcome the amount of heat generated. Most computers have internal fans that operate continuously whenever the computer is turned on. However, there are other cooling methods that prevent or minimize the use of fans.
These include more passive ways of cooling such as semi-fanless technology and various types of methods that don’t require fans.

Fanless Cooling Technology

What is a semi-fanless PSU?

A power supply unit (PSU), like the name suggests, supplies the computer with electrical power. The PSU converts the alternating current from a power source to a low voltage direct current. Doing so ensures that the computer has the correct electrical voltage to operate. This process is not entirely efficient though and energy will be lost. The lost energy will be converted to heat, making the PSU susceptible to overheating.
To cool the PSU, semi-fanless technology can be used. A semi-fanless PSU still has a fan, except it only turns on when required. This means that the fan is not running constantly and will only turn on when the PSU reaches a specific temperature. Sensors within the PSU will detect the temperature increase and turn the fan on if needed. As the temperature drops, the fan will turn off.

Fanless cooling vs Fan cooling

Fanless cooling uses passive techniques to prevent the computer components from overheating. A range of technologies can be used for passive cooling, such as heat sinks and heat pipes. However, while there are several advantages to using these methods, some disadvantages are worth noting.

Advantages of Fanless cooling

The main advantage of fanless cooling is noise reduction. Many people will switch to a semi-fanless or fanless system instead because the noise from a constantly running fan can get quite annoying. The noise from a fan worsens when the work demand for the computer increases. With the increased output, computers need more energy, which means more heat is generated. To counteract this heat, the speed of the fans will increase. Fanless cooling is quieter in comparison to fan cooling because there is less sound.
Besides noise reduction, there is also a reduction in the weight and size of the electronic device. When fans are included in the design, they can make the device bulkier or bigger than what it should ideally be. Some methods of fanless cooling, such as Vapor Chambers, are extremely thin and do not require much room. This means that the device is more compact and there is some extra space if needed.
Another advantage is that fanless technology eliminates mechanical failure as there are no moving parts. Like any machine, moving parts degrade over time and eventually become faulty. Since computers are reliant on fans to prevent overheating, it would be detrimental to the computer if the fan were to stop working. With fanless cooling, there is no need to worry about mechanical failure and regular maintenance for a fan is not required.
Lastly, fans cool a computer by generating airflow. However, this movement of air is not ideal in all locations. For example, workplaces that need to be kept sterile, such as operating rooms or laboratories, need to minimize the airflow significantly. Otherwise, unwanted microbes and debris could circulate in the room. Again, fanless technology is advantageous because it does not generate an airflow.

Disadvantages of Fanless cooling

The main disadvantage is that fanless cooling is less effective than fan cooling. In addition, once the passive cooling methods are exhausted, the components could overheat if there is no fan for backup. Because of this, fanless cooling is not ideal in hot locations because the risk of the computer overheating is too high.
Another disadvantage is that many people think the computer will be completely silent once they switch to fanless cooling. But despite eliminating the fan, there will always be some underlying electrical sound that can be heard. Unfortunately, this sound is unavoidable.

How Fanless Cooling Works

There are several fanless methods for cooling vital components, such as the central processing unit (CPU). Fanless cooling has successfully worked for the CPU due to several mechanisms such as heat sinks, heat pipes, Peltier modules, and Vapor Chambers. Here we will discuss these mechanisms in further detail.

Example use in CPU

The CPU is like the brain of the computer, containing many electrical circuits involved with programming and memory. When computer activity increases, so does the activity of the CPU and more energy is required. Again, with any electrical component, there is the potential for it to overheat when more power is needed.
Ensuring that the CPU does not overheat is vital since the computer is reliant on the CPU to function. While fans are typically used to cool the CPU, fanless technologies also work.

Types of fanless cooling technology

Heat sinks

A passive heat sink is a component that gradually transfers heat away from the CPU. The heat is transferred by conduction, a natural process that transfers heat to a cooler object. In this case, the heat from the CPU is transferred to the heat sink. To facilitate this process, heat sinks are composed of metals such as aluminum or copper because they have a higher thermal conductivity. The thermal conductivity is crucial because it determines how much heat is transferred from the CPU to the heat sink.
Another crucial factor that increases the amount of heat loss from the CPU is the surface area of the heat sink. Heat sinks with more surface folds have a greater surface area. With a greater surface area, more heat can be expelled from the heat sink, and thus more heat can be transferred away from the CPU.

Heat pipes

Heat pipes also transfer heat away from the CPU. Inside the pipes is a heat transfer liquid, which evaporates by removing latent heat. The heat transfer fluid that becomes vapor carries the heat to the cooler end, thereby releasing heat.
Hence, there are two phases, the liquid phase, and the gas phase. As the gas cools, it will return to the liquid phase and release more heat energy. The liquid will move back towards the hot end, generating a current that constantly moves heat away from the CPU.

Peltier modules

Peltier modules harness the Peltier effect to minimize heat through thermoelectric cooling. Peltier modules are also known as thermoelectric modules. When an electrical current passes through these modules, the module can have a cooling or a heating effect.
Therefore, when heat passes through the module, it will be cooled. The cooling effect works best when the electrical circuits contain more than one type of semiconductor.

Vapor Chambers

Vapor Chambers are based on the technology of heat pipes. Instead of using individual pipes, a chamber is used instead. The same principle applies – heat is instantly transferred away from the CPU by vaporization and condensation. Vapor Chambers can dissipate heat more quickly due to the greater thermal conductivity.

Introduction to DNP's Vapor Chamber

Vapor Chambers are undoubtedly one of the best methods for passive heat transfer, and DNP’s Vapor Chamber has some unique features. This Vapor Chamber is extremely thin, 0.20 mm to be precise. Hence, it has a much greater degree of thermal conductivity when compared to others. Additionally, it is flexible and can be applied to almost any component regardless of the shape. It will easily bend around curved or graded edges.
Due to how thin and flexible this Vapor Chamber is, it can be used for various devices, especially those which are small, light, or oddly shaped. For wearable electronics, this will lead to endless potential. Not only will it reduce the weight and cool the device optimally, but it also means that more significant amounts of data can be handled.
Overall, there is vast potential in DNP’s Vapor Chamber given the huge range of electronic devices it could be applied to. (* Information as of February 2022)

DNP's Vapor Chambers

Other columns and featured articles

See 11 related fields