Computer cooling

A CPU Cooler Heatsink are called, which are designed to meet the special requirements of cooling of microprocessors. It is usually cooler fan combinations, sometimes also only passive cooler or water cooler.

Task

Microprocessors generate during operation, like all semiconductors, heat. To prevent overheating, which can lead to malfunctions or to the destruction of the components, the natural heat radiation is not sufficient for modern processors for personal computers. In order to guarantee an optimal cooling, the heat must be dissipated by the processor core and the heat-emitting surface can be increased as quickly as possible. This is done with heat sinks that are usually made ​​of aluminum, are made in some cases, fully made ​​of copper, and usually in addition to the heatsink mounted fans. When a heat sink made of aluminum and copper, it is called a hybrid cooler.

Special

Processor cooler differ in some details from other heatsinks and must meet some special, sometimes contradictory requirements.

• You must be both mechanically and always adapted in performance on the respective processor or socket type. Almost every new processor generation requires new and more powerful because of the increasing power losses cooler.
• Direct installation at the processor socket, or the motherboard forces for reasons of mechanical stability, limitation of weight. Manufacturers shall indicate in modern systems to ensure maximum values ​​.
• The cooling effect can be substantially improved by the use of fans, but this increases noise pollution. While this usually does not interfere in server rooms, it is important when workstations on the observances of health and safety regulations and, where possible, to seek quiet systems.
• Unlike power semiconductors with their usually large contact areas with waste @ processors on a very small area so that the heat transfer between the processor and cooler great attention must be placed on. Modern CPUs and GPUs to achieve power dissipation of partially well over 100 watts on a surface that can be smaller than a fingernail. By comparison, the 18- cm - hotplate of a conventional electric range achieved just seven to ten W / cm ².

Cooling types

A basic distinction between

Alternatives

A new generation of processor coolers works with heat pipes ( engl: heat pipes ). Heat pipes are - to put it simply - thin tubes, usually made ​​of copper, where there is a transport medium (a special liquid or gas ) that is transported in contrast to metal, the heat is not by management but by convection. This transport medium is then off the heat to the cooling fins, which must have no direct connection to the processor. Thereafter, the cooled transport medium reaches back to the processor, where it can add new heat. These coolers are usually larger than their predecessors, under certain circumstances without a fan and then also work completely silent. Usual case for personal computers are usually not optimally designed for this type cooler, because too much heat builds up, which is why most have an additional fan should be used.

Another way is cooler, composed of aluminum and copper, known as hybrid heat sink, but in most cases a conventional fan. Here, the advantages of both metals are optimally used: Copper conducts heat quickly from the CPU core ( The ) away, the aluminum saves over solid copper heatsinks costs and especially weight.

Fan noise

The fans of active processor coolers cause noise during operation. Typical sizes for the assessment of the noise, the loudness of the sound pressure levels or sound power levels. The loudness is usually given in Sone. Sound pressure level and sound power levels are usually expressed in decibels ( dB ( A)) or Bel.

Passive CPU coolers operate silently because no moving parts are present. They can only be used for applications where processors implement as little power into heat that passive cooling is sufficient.

The most commonly used today main processors in PCs require active cooling. Depending on the size of the heat sink used varies the cooling performance. Also, the cooling performance is also related to the volume flow of the air blown through the radiator air.

Large fans who come to large coolers to use, produce the required flow rate at lower speeds than small fans that come on smaller coolers are used. These large, slowly rotating fan audibly produce less noise than small, fast- spinning fans.

Graphics card manufacturers who use lack of space, often only small fan with a correspondingly high speed. However, it also became apparent, a trend towards large-scale heat sinks from which are then passively cooled or use fan with larger diameters.

To reduce the volume of the fans can be operated at a reduced voltage they are often (e.g., 7 volts instead of 12 volts). Also active fan controllers can reach this purpose used, including by means of pulse width modulation ( 4-pin connector ). But we must note that such a reduced cooling capacity is still sufficient to keep the temperature within a desired range.

Since office noise is considered as a stress factor and also a health hazard, may, for example, in Austria according to statutory provisions in the simple work 70 dB (A ) and mainly mental work 50 dB (A ) are not exceeded.