Quiet PC

With noise reduction in personal computers concepts are referred to personal computers aimed at the lowest possible noise level in operation. These concepts can be offered in a sellable PCs or caused by subsequent modifications or extensions.

Current PCs develop in operation in some cases very much heat. During the first PCs exhibited an electric power consumption of a few watts, and did not require active cooling, increased over time, the electric power consumption, and thus the heat output of the PC.

Noise sources

The sources of noise in a personal computer can be divided into two main categories:

• Fan,
• Mechanically driven drives.

Current personal computers often have high power dissipation in the range of about 100 watts, with the use of powerful processors and graphics cards also about 300 watts, which is almost fully implemented already in the housing to heat. To preserve the installed components from damage due to overheating, both the housing, as well as individual components, such as processor, power supply and graphics card are equipped with appropriately powerful, but often loud fans.

More noise polluters are primarily hard drives and optical drives, some of which operate at speeds of over 10,000 rpm. Furthermore, vibrations can be transferred to other parts such as housings and this stimulated by resonance effects of noise.

In addition, it can come in different frequency ranges by capacitors, inductors and other vibrating components in the power supply to noise. In liquid crystal displays occur in some models humming or buzzing sounds, in part, a function of the selected brightness setting. Some mice also give quiet sounds.

Target

The computer is up to 24 hours a day, so that the operation noise can be disturbing in use particularly in the living room or bedroom. Even with the office work and media center PCs in the living room can be any noticeable noise will be perceived as unpleasant.

A particular challenge is to get quiet and at the same time powerful computer. The partial high power consumption of high-end components, how they are used, for example, in computers that are used to play, and the associated waste heat better overall cooling is necessary.

Measures

The simplest and most useful way to get a quiet computer is to buy a device that is optimized for low noise. However, this does not fall under the term silencing, as hereby active intervention is referred to in a given computer. Due to the often necessary technical and structural changes silencing is also related to the case modding.

Quiet components

• Passive or particularly quiet cooler for processors
• Passive or particularly quiet cooler for graphics cards
• Other parts (eg insulation mats for the housing, quiet case fan or water cooling). A water cooling system is just one way of noise reduction and not necessary to get absolutely a quiet computer. Sometimes can also be annoying to hear the necessary pump.

In addition, the use of components with low power dissipation makes sense. These produce in relation to performance less waste heat, which causes that must be cooled less expensive as a result.

Power Supply

The fans of traditional power supplies are often quite noisy, as they run in every operating phase with maximum number of revolutions. This can be reduced by a temperature- regulated power supply noise output. The operating voltage of the fan is controlled by the temperature of the secondary rectifiers, which has an effect on power consumption, noise, and air flow speed. Moreover, there are so-called silent power supplies that are equipped with a larger inner 120 to 140 mm fan and can rotate slower due to the larger volume of air promotion. The opposite effect occurs with flat power supplies and power supply modules, which are equipped with 40 mm fans. A simple fan can be replaced with one with a better ratio in airflow to noise from the manufacturer, because the power supply is sealed and is subject to a dying product liability in case of breakage. There are passively cooled power supplies, they have no fans and are available and comparatively expensive only in the low to mid segment of output power (up to 560 W).

Was contrary to the original ATX concept, in which the power supply (top mounted) responsible for the ventilation of the entire housing, offer newer ATX case the possibility to install the power supply down and thus can be directly supplied with cooler outside air. Then separate case fan is responsible for cooling, two separate cooling circuits there are to a certain extent created. A side-effect is the increased longevity of the power supply, since it is no longer driven in the direction of the heated air inside of the housing.

Processor cooler

Wherein the processor cooling should be noted that a cooling body with a very good thermal conductivity is used (for example, with a copper core ). Cheap fans are often unregulated, so run with constant 12 volts. Adjustable fan can be identified by three or four instead of two connecting cables, the speed is controlled by the motherboard via pulse width modulation. A free software for fan control, for example SpeedFan.

A major shortcoming in the cooling by means of heat sink and fan is the fact that the heated exhaust air is not usually blown out like the power supply, but is moved to a large extent in a circle, whereby only a portion of the heat generated actually the airflow through the PC case is removed. Remedy the direct aspiration of room air via a plugged pipe to the fan, what the PC case, however, must have an appropriate opening. One advantage of the fresh air intake is lower fan speeds that are sufficient to cool the CPU. However, the heat sink more rapidly dust and the noise of the fan can also access directly to the outside.

Graphics Card

When you buy the graphics card should already be taken to a good and quiet cooling the GPU, that on a subsequently modified graphics card cooler will void your warranty. Here the same applies as for the processor that a noisy cooling does not necessarily mean good cooling performance. Meanwhile, some very good and quiet VGA cooler on the market, passively cooled graphics card with GPU are also available.

Northbridge cooler

Some motherboards also the Northbridge is equipped with an active cooler. On the one hand, to address overclockers, but also because of the high heat dissipation current chips. Due to the mostly small -sized space on the motherboard often very fast moving 40 -mm fans are used here. The exchange of these fans has usually loss of warranty. The use of conventional passive Northbridge cooler is very dangerous, as these overheat then quickly especially with the new chipsets, which results in a total failure of the main board after themselves. An exception are passive cooler with heatpipes that dissipate the waste heat to a larger fan or a generously sized passive cooling element.

Hard Drives

Transfer to a metallic hard drive bay removable hard drives inevitably their vibrations to the housing. The hard drive manufacturer Seagate states that approximately 70 percent of the sound produced from a hard drive be issued a so-called structure-borne noise. Therefore Hard drive decoupler are often an effective way to reduce the noise of the hard drives.

These are available as ready- mounting frame and brackets, where the disks are separated from the housing by rubber. Some of these solutions provide additional cooling functions for the hard drive. However, such cages usually have to be installed in a 5.25 "bay of the computer case.

A very convenient, but questionable Entkoppelungsmethode is a suspension via conventional Einmachgummis. However, such self-made solutions are relatively uncertain, as the elastomer used may not withstand the stresses permanently. In addition, is given in the data sheets to screw the hard drive permanently. If the hard drive is not fixed against natural vibration is to be expected with a loss of speed and premature bearing failure.

In decoupling on a disk should be used, which gives it passively as surface- fin cooler or active with one or two fans in the trade as a cooling solution HDD Coolers.

In benchmark tests, it was found that the access times can easily deteriorate with soft suspended disks. This change is in most cases, however, so marginal that in practical operation, no performance difference was found.

A silent alternative to the hard drive solid state drives. These semiconductor memory contain no moving parts and are completely silent.

Housing design

Also a good workmanship and a clean installation of the internal cables may provide in connection with good housing design for an air draft (English Airflow ), which provides for a total of more efficient cooling, which in turn is rewarded with a low noise level. Ultimately, you can achieve a lower noise level by individual, structural changes to the computer or individual components.

Insulation

Even later Schalldämmmatten can be glued into existing computer. This filter from the inside of the PC coming out high frequencies. However, one should not overestimate the caution, because the temperature inside rises through these mats by 2 to 3 ° C at. In addition, these Schalldämmmatten are relatively expensive.

Another possibility is a insulating mats that are based on bitumen and are sold actually for car hi-fi purposes. Due to their weight, they should prevent the emergence of resonance effects. The high basis weight of these mats but has the disadvantage that a maxi - Tower by around two to 3 kg can be severe.

Also, individual components can be insulated. One example is the so-called Bitumenbox, when a hard drive is installed in an old 5.25 CD -ROM case and wrapped in special insulating boards made of bitumen. This makes disk are significantly reduced among other things, the high-frequency noise when running.

Temporarily turning of components

This is possible, for example by switching the fan only as needed using thermostats. This so-called semi-passive cooling does allow temporarily a reduced volume. Also, hard drives, inter alia, can be switched off after a certain idle time.

Spatial separation of PC and PC workstation

A placed in the next room PC is not audible usually at work. If the spatial possibilities exist to this is a very effective and inexpensive method for noise reduction. The cable can be made by a small wall opening in the form of empty socket housings on both sides of the wall. The disadvantage is that the operation of the device ( turning; drives use ) Extra the next room must be consulted.

An elegant but expensive solution is to use a KVM extender. Depending on the distance, financial resources and requirements - - Here the video, keyboard and mouse signals over Cat - be or fiber-optic cable between the PC and peripherals replaced. Even more expansive ways provides a thin client that is a complete small computer for its part, but produces less heat and noise as well as any necessary terminal server.

Potential Hazards

Potential hazards during processing or altering the components are

• The electromagnetic compatibility of the instrument may be impaired
• Health risks posed by improperly made ​​working on parts, especially at the power supply. Here is the original fan often replaced with quieter versions. Especially in open power supplies there is a risk of electrocution, even when they are disconnected from the power supply.
• Damage to hardware or loss of warranty and guarantee claims. When the hardware has changed (eg by opening of power supplies, but not your installation or replacement of entire components such as memory, etc.) you lose typically the warranty and any warranty. The internal components can be damaged especially in insufficient cooling or improper handling.
• When components are insufficiently cooled shortening the life

Noise measurement

For computers, two different units for the classification of the noise generated by the device are used: The decibel scale and the sone scale.

However, the decibel scale tells very little about the sound pressure level of a noise, but not about his perceived annoyance. Therefore, the decibel scale is only suitable to make statements about the Leisigkeit the fault ( or lack thereof) in computers. The sone scale, however, tried to express the human sense of annoyance in easily comparable figures.

To select components for Silent PCs, the values ​​of the following table can be regarded as orientation, it must be ensured that only those measured values ​​are comparable to those determined under the same conditions. The most crucial factor is the microphone closer to the sound source. Is not clear whether two measurements of this distance was the same, a comparison of the values ​​is meaningless.

When in doubt, but you should not do without a trial hearing.