Comparison be quiet! Dark Rock TF vs be quiet! Dark Rock Pro 3

The direction in which the active cooler (see "Type") airflow exits.

This parameter is relevant primarily for models used with processors, but the options can be as follows:

— Sideways (scattering). Operation format typical for coolers of the so-called tower design. In these models, the fan is mounted perpendicular to the substrate in contact with the processor, due to which the airflow moves parallel to the motherboard. This ensures maximum efficiency: the heated air does not return to the processor and other system components, but is dissipated in the case (and almost immediately goes outside if the computer has at least one case fan). The main disadvantage of this option is the large height of the structure, which can make it difficult to place it in some system units. However, in most cases this point is not fundamental — especially when it comes to a powerful cooling system designed for an advanced system with a performant "hot" processor. So, it is side dissipation that is the most popular option nowadays — especially in coolers with a maximum TDP of 150 W and higher (although more modest models often use this layout).

— Down (to the motherboard). This format of operation allows you to "lay" the fan with a heatsink flat on the motherboard, significantly reducing the height of the entire cooler (compared to models using side blowing). On the other hand, this format of...work is not very efficient — after all, before dissipating through the case, hot air again blows over the board with the processor. So nowadays, this option is relatively rare, and mainly in low-power coolers with an acceptable TDP of up to 150 W. And you should pay attention to such models mainly when there is little space in the case and a small cooler height is more important than high efficiency.

A feature found in some active CPU coolers (see "Intended Use").

For tower arrangements in general, see Airflow Blowing below. And the double-tower design means that the cooler has two working blocks — that is, two fans and two radiators. Accordingly, there are more heat pipes in the design than in single-tower models — at least 4 of them, and more often 5 – 6 or even more. Such an arrangement can significantly increase the cooling efficiency; on the other hand, it also significantly affects the dimensions, weight and price.

The maximum TDP provided by the cooling system. Note that this parameter is indicated only for solutions equipped with heatsinks (see "Type"); for separately made fans, the efficiency is determined by other parameters, primarily by the air flow values (see above).

TDP can be described as the amount of heat that a cooling system is able to remove from a serviced component. Accordingly, for the normal operation of the entire system, it is necessary that the TDP of the cooling system is not lower than the heat dissipation of this component (heat dissipation data is usually indicated in the detailed characteristics of the components). And it is best to select coolers with a power margin of at least 20 – 25% — this will give an additional guarantee in case of forced operation modes and emergency situations (including clogging of the case and reduced air exchange efficiency).

As for specific numbers, the most modest modern cooling systems provide TDP up to 100 W, the most advanced — up to 250 W and even higher.

The highest speed at which the cooling system fan is capable of operating; for models without a speed controller (see below), this item indicates the nominal rotation speed. In the "slowest" modern fans, the maximum speed does not exceed 1000 rpm, in the "fastest" it can be up to 2500 rpm and even more.

Note that this parameter is closely related to the fan diameter (see above): the smaller the diameter, the higher the speed must be to achieve the desired airflow values. In this case, the rotation speed directly affects the level of noise and vibration. Therefore, it is believed that the required volume of air is best provided by large and relatively "slow" fans; and it makes sense to use "fast" small models where compactness is crucial. If we compare the speed of models of the same size, then higher speeds have a positive effect on performance, but increase not only the noise level, but also the price and power consumption.

The total time that a cooling fan is guaranteed to run before it fails. Note that when this time is exhausted, the device will not necessarily break — many modern fans have a significant margin of safety and are able to work for some more period. At the same time, it is worth evaluating the overall durability of the cooling system according to this parameter.

The standard noise level generated by the cooling system during operation. Usually, this paragraph indicates the maximum noise during normal operation, without overloads and other "extreme".

Note that the noise level is indicated in decibels, and this is a non-linear value. So it is easiest to evaluate the actual loudness using comparative tables. Here is a table for values found in modern cooling systems:

20 dB — barely audible sound (quiet whisper of a person at a distance of about 1 m, sound background in an open field outside the city in calm weather);
25 dB — very quiet (normal whisper at a distance of 1 m);
30 dB — quiet (wall clock). It is this noise that, according to sanitary standards, is the maximum allowable for constant sound sources at night (from 23.00 to 07.00). This means that if the computer is planned to sit at night, it is desirable that the volume of the cooling system does not exceed this value.
35 dB — conversation in an undertone, sound background in a quiet library;
40 dB — conversation, relatively quiet, but already in full voice. The maximum permissible noise level for residential premises in the daytime, from 7.00 to 23.00, according to sanitary standards. However, even the noisiest cooling systems usually do not reach this indicator, the maximum for such equipment is about 38 – 39 dB.

Number of heat pipes in the cooling system

The heat pipe is a hermetically sealed structure containing a low-boiling liquid. When one end of the tube is heated, this liquid evaporates and condenses at the other end, thus removing heat from the heating source and transferring it to the cooler. Nowadays, such devices are widely used mainly in processor cooling systems (see "Intended use") — they connect the substrate that is in direct contact with the CPU and the heatsink of the active cooler. Manufacturers select the number of tubes based on the overall performance of the cooler (see "Maximum TDP"); however, models with similar TDPs can still differ markedly in this parameter. In such cases, it is worth considering the following: increasing the number of heat pipes increases the efficiency of heat transfer, but also increases the dimensions, weight and cost of the entire structure.

As for the number, the simplest models provide 1 – 2 heat pipes, and in the most advanced and powerful processor systems, this number can be 7 or more.

The type of contact between the heat pipes provided in the heatsink of the cooling system and the cooled components (usually the CPU). For more information about heat pipes, see above, and the types of contact can be as follows:

— Indirect. The classic version of the design: heat pipes pass through a metal (usually aluminium) base, which is directly adjacent to the surface of the chip. The advantage of such contact is the most even distribution of heat between the tubes, regardless of the physical size of the chip itself (the main thing is that it should not be larger than the sole). At the same time, the extra piece between the processor and the tubes inevitably increases thermal resistance and slightly reduces the overall cooling efficiency. In many systems, especially high-end ones, this drawback is compensated by various design solutions (primarily by the tightest connection of the tubes with the sole), but this, in turn, affects the cost.

— Direct. With direct contact, the heat pipes fit directly on the cooled chip, without an additional sole; for this, the surface of the tubes on the desired side is ground down to a plane. Due to the absence of intermediate parts, the thermal resistance at the places where the tubes fit is minimal, and at the same time, the radiator design itself is simpler and cheaper than with indirect contact. On the other hand, there are gaps between the heat...pipes, sometimes very large — as a result, the surface of the serviced chip is cooled unevenly. This is partly offset by the presence of a substrate (in this case, it fills these gaps) and the use of thermal paste, however, in terms of uniformity of heat removal, direct contact is still inevitably inferior to indirect contact. Therefore, this option is found mainly in inexpensive coolers, although it can also be used in fairly performant solutions.

The material from which the substrate of the cooling system is made is the surface that is in direct contact with the cooled component (most often the processor). This parameter is especially important for models with heat pipes (see above), although it can be specified for coolers without this function. Options can be as follows: aluminium, nickel-plated aluminium, copper, nickel-plated stranded. More about them.

— Aluminium. The traditional, most common backing material. At a relatively low cost, aluminium has good thermal conductivity characteristics, is easy to grind (required for a snug fit), and well resists scratches and other irregularities, as well as corrosion. However in terms of heat removal efficiency, this material is still inferior to copper — however, this becomes noticeable mainly in advanced systems that require the highest possible thermal conductivity.

— Copper. Copper is noticeably more expensive than aluminium, but this is offset by higher thermal conductivity and, accordingly, cooling efficiency. The noticeable disadvantages of this metal include some tendency to corrosion when exposed to moisture and certain substances. Therefore, pure copper is used relatively rarely — nickel-plated substrates are more common (see below).

— Nickel-plated copper. Copper substrate with an additional n...ickel coating. Such a coating increases resistance to corrosion and scratches, while it practically does not affect the thermal conductivity of the substrate and work efficiency. However this feature somewhat increases the price of the radiator, but it is found mainly in high-end cooling systems, where this moment is almost invisible against the background of the overall cost of the device.

— Nickel-plated aluminium. Aluminium substrate with an additional nickel coating. For aluminium in general, see above, and the coating makes the heatsink more resistant to corrosion, scratches, and burrs. On the other hand, it affects the cost, despite the fact that in fact, pure aluminium is often quite sufficient for efficient operation (especially since this metal itself is very resistant to corrosion). Therefore, this variant was not distributed.