A fanless PC from the high-end sector? A future wish that’s become a "reality"
High performances can only be made possible with the production of lots of waste heat, and this result in correspondingly noisy ventilation systems. This principle has been preserved in the core, since the development of modern PCs. Even computers from the premium segment still rustle distinctly in the background. The users of the high-end devices – gamers, graphic designers, developers, film producers – tend to appreciate a quiet environment. That’s how the desire for silent computers with high performance was soon born. However, its implementation did not seem possible for a long time. Now different manufacturers have shown that a fanless top-class PC does not have to remain a dream. The first models are already available on the market and show a lot of potentials for the future.
High-end versus waste heat - the heat problem of high-performance processors
Where does most of the heat in the computer come from? The main heat sources are the processors and the chips of the graphics cards. They generate waste heat with each switching process. This also explains why processors with a high cycle frequency are affected by the heat problem: Since, particularly large number of switching operations takes place there. In addition, the components are extremely small, thus making the heat to be generated in a very small space. As such, those who rely on strong cores could therefore not cope, without active ventilation. The general rule is to have fans above the graphics card, and above the processor, in addition to those of the case. These create a constant background noise through the simple movement of their blades. Although water cooling is the alternative method, this is complex and not easy to handle. As a result, modern PCs hum monotonously during their operation. Unpleasantly, the speed of the fans, as well as noise increases with increasing load on the components. So far, it’s been true that: Powerful PC are not silent, and a low-noise PC are not powerful.
A fanless PC: old idea, modern implementation
Why is a PC without ventilation considered particularly attractive? Above all, this is due to the disturbance factor which constant fan noise has on the users. In addition, there is a risk that the fans clog and overheat the components. Many developers or designers have sat in front of their rustling laptop and wished there was some silence. This is a desire which has now been answered.
Truly, the idea of fanless cooling is not new. In fact, the first computers that ran under DOS were so slow that they did not need fans. The active cooling was only necessary with increasing performance. There are also modern computer variants that can operate without the circulation of air. Good examples are tablets and smartphones. Here, however, the fan problem was solved at the expense of performance. Mobile processors have to content themselves with less power and thus generate less heat. With old or throttled CPUs, however, a silent PC cannot be transferred to the high-end sector. Other techniques are needed here.
Passive cooling for high-end computers
Intelligent passive cooling techniques are the solutions, in running high-performance computers without ventilation. The basic structure works as follows: The heat from the CPU and GPU is quickly dissipated via highly conductive materials. The corresponding component is referred to as a heat pipe and is connected to the other side through what’s known as a convector. This must meet various requirements. First, a high heat capacity and good conductivity are important. However, this will still not solve the problem: Since the heat reservoir would eventually get full, even if is very large, and would no longer be able to cool the processors. At the end, the heat must therefore have to be transmitted back into the ambient air.
Transmission of waste heat
To transmit the waste heat without artificial air flow, large surfaces are required. The convectors are thus particularly shaped. Additionally, the enclosure of the fanless high-end PCs is used for the transmission of heat. This offers sufficient space that is cooled by the air in the room. Here again a well-known trick is used: The heat exchangers are designed so that air can pull through. When the gases heat up inside, they expand, become lighter than the ambient air and consequently rise upwards. This creates an airflow inside the exchanger, even without fans. This is called chimney effect and can be observed in every chimney.
Benefits from passive ventilation
If you want to benefit from a noiseless, passively-cooled PC, you now have the opportunity to do so in the high-end sector. In everyday use, the whisper-quiet PCs do not differ in terms of performance from their actively cooled counterparts. Likewise, the appearances of the future-oriented models are very modern. You would only have to support the passively cooled computer a little, while it is being set-up. In order for the heat transfer to the air to function well, the sides of the housing should be free. In principle, this applies to all devices with active cooling. This means: Do not place the tower right next to a wall; do not hide it behind a curtain, and do not place it in a cupboard. In this way, you’ll be able to enjoy even longer maintenance intervals: Where no active ventilation is available, no fans can become clogged with dust.
Silent PCs: all components must fit
If you truly want a silent model when buying a new PC, all the components must fit this plan. Although eliminating the fans eliminates the loudest elements, other non-silent parts may remain. This includes the traditional HDD hard drive, which rotates when reading and writing. The modern SSD storage is much quieter and equally very fast. However, there currently exists even more expensive (storage models) with comparable capacity. Alternatively, the HDD can be housed in a sound-absorbing housing. Another source of noise is the power supply. Of course, this doesn’t need ventilation, if it is intended for a very quiet high-end PC. Corresponding models are available on the market. In general, a modern PC with the requirement of “quiet to noiseless” is best bought as a complete set; since this will not only reduce the purchase price, but will also be the best guarantee that all components meet the desired target.
Risk of burning / blowing? No danger
With passive cooling, is there a danger that the device overheats? No. In modern PCs, the temperature in the interior is continuously monitored by sensors – this also applies to all fan-cooled models. Should a component be in danger of overheating, an emergency stop can occur. However, users of current devices usually only know about this problem from narratives of the past. The technical development is so advanced that such a step is no longer necessary in an intact computer.