Performance parameters for CPU fans

Hot summer is coming, people are thinking about how to cooling at the same time, will certainly be thinking how to let the computer "cool a summer." So how are we going to cooling the computer? Generally speaking, we can use air-cooled, water-cooled, semiconductor refrigeration and fluorine (nitrogen) refrigeration and other methods to cool down, but because these methods to achieve high cost, but also may be a threat to computer security, so these kinds of methods are not very popular in the country. Compared with these methods, the other most effective, most convenient and most commonly used method is to use the fan and heatsink. When it comes to the CPU fan and heatsink, in fact, it is to use them to quickly transfer the heat of the CPU and blow to the nearby air, cooling effect directly with the CPU cooling fan, the quality of the heatsink, so how to choose a suitable CPU fan has become a topic of great concern to us. But because the market is full of fake and shoddy products, if we do not understand the basic knowledge of the CPU fan, then in the purchase process is very easy to be deceived. Therefore, before we buy the fan, it is necessary to understand some of the CPU fan performance parameters, once you know the identification criteria, I believe you will definitely choose a practical and appropriate fan. Below, the author of the CPU fan on several main performance parameters introduced to everyone, hope to be helpful to everyone.

1. Fan Power

Fan power is an important condition that affects the cooling effect of the fan, the greater the power, the stronger the wind force of the fan, the better the effect of heat dissipation. The fan power and fan speed is directly linked together, that is, the higher the fan speed, the fan will be more powerful. At present, the general computer market is sold on the DC 12V, the power is from 0. x Watts to 2.X Watts, the power size of which needs to be based on your CPU heat to choose, in theory, choose a slightly larger power some better, because the fan speed is higher. But I also want to remind you here that can not be one-sided emphasis on high power, which needs to match the power of the computer itself, if the power is too large, not only can not play a very good cooling effect, but may aggravate the workload of the computer, which will produce vicious cycle, and ultimately shorten the life of the CPU fan. Therefore, when selecting the CPU fan power size, you should follow the principle of adequacy.

2. Fan caliber

This performance parameter has a direct influence on the airflow of the fan, it indicates that the larger the caliber of the fan within the allowable range, the larger the air flow of the fan, and the greater the effect surface of the wind force. Usually the reservation in the host box is the installation of 8cmx8cm axial flow fan, if not in the standard location installation is not the limit, then we can choose a slightly larger size of the fan. For this indicator, I would like to say that the choice of fan caliber must be compatible with the chassis structure of their own computer, to ensure that the fan does not affect the normal work of other computer equipment, and to ensure that the computer chassis has enough free space to facilitate the demolition of other accessories.

3. Fan speed

Fan speed and fan power is inseparable, the speed of the size of the direct impact on the size of the fan power. In general, we believe that, within a certain range, the higher the speed of the fan, the higher the amount of air it transmits to the CPU, the better the cooling effect the CPU will get. But once the fan is spinning more than its rated value, the fan is working under a long period of time overload, itself will produce heat, the longer the more the heat generated, the fan not only can not play a very good cooling effect, but will "water on fire"; In addition, the fan in the process of high-speed operation, may produce very strong noise, Long time may shorten the fan life, and higher operating speed requires greater power to provide "power source", and high power source is from the motherboard and power in the high power, the motherboard and power supply in the overload power will often cause system instability. Therefore, we choose the speed of the fan, should be based on the calorific value of the CPU, it is best to choose the speed of 3500 to 5200 revolutions between the fan.

4. Fan material

Because the CPU's heat is transmitted through the heatsink, and then the cooling air blowing through the fan to take away the heat of the heat sink, and the heat of the fan can be transmitted by the composition of the thermal conductivity of the material of the film decided, so the material quality of the fan on the heat conduction performance has a decisive role, For this reason, we must pay attention to the fan thermal conductivity of the heat conductive film is good. At present, the thermal conductivity of the material, the best thermal conductivity of course is gold, gold platinum are good, the reason why AOpen of the AX6BC series motherboard in the North Bridge chip heatsink on the gold plated, on the one hand is to show the status of Noble, on the other hand, is conducive to heat dissipation. The conductive metal next to gold is copper. Copper is a good thermal conductivity of metal, if the use of copper to produce heat sinks, the cooling effect will be very ideal, but the copper texture is stronger, processing more difficult, heavier quality, and higher costs, so we are currently very difficult to see the use of copper to produce heat sinks. Again in copper is iron and aluminum, these two are very popular metal, but both horizontal comparison, you will find iron rust, texture hard, difficult to process, quality and other weaknesses, and aluminum is not such trouble, so aluminum becomes the best material for the production of heat sinks.

5. Fan Noise

Another external manifestation of the quality of the fan is the noise level. Imagine, if buy back fan noise is very large, even if the fan other performance is very good, their heart is not steadfast, because too much noise will greatly affect our operation of the computer mood. The noise size is usually related to the power of the fan, usually the larger the power, the faster the speed, at this time a negative effect is displayed, that is noise. So, when we buy the fan, be sure to try to listen to the noise of the fan, if too large, then it is best not to buy; Of course, the fan noise, not necessarily the quality of the fan problem, it may be the fan shaft lubrication effect is not good, or the fan is not properly installed, if so, We'd better be able to reposition the fan, or add some lubricant to the fan shaft to ensure that the lubrication works well. Now fans have put in some design to reduce noise, such as changing the angle of the fan blades, increasing the lubrication and stability of the fan shaft. We use lubricating oil lubrication bearings, because the operating time is not long it is very easy to cause overheating of the machine and the crash phenomenon, serious time may also burn the movement. For this reason, many good brand fans are starting to use ball bearings, which use many steel balls as a medium to reduce friction. This kind of ball fan is characterized by high wind, long life and low noise, but the cost is higher, only high-end fans may use it, and for ordinary fans, although it is called "bearing", but only bearing bearings, that is, made of copper jackets and steel shaft core, and "ball bearing" but completely different. In addition, the author here also want to emphasize that the fan rotation should be smooth, otherwise it is easy to generate noise, so we buy the fan, we must remember to check the fan roller axis is loose.

6. Fan shape

We refer to the shape of the fan, usually the shape of the heatsink that makes up the fan. As the fan shape on the wind and exhaust impact is very large, and the wind and exhaust will directly affect the final cooling effect, so in a sense, the fan shape on the performance of the fan also has a certain impact. Ordinary heat sink is die-casting, the common shape is just a few more leaves of the "leek" zigzag, the heat sink heat effect is the most common. The more high-grade heat sinks use the aluminum mold through the lathe turning, the shape after turning is a plurality of columnar protrusion, this kind of radiator is used in the high-end graphics card and some foreign original machine CPU (there are many foreign original machines do not use the fan at all, only use this kind of heat sink). There is also a fin-shaped radiator, which is folded through a thin sheet of aluminum, and looks like an accordion bellows, which has a good cooling effect. The more upscale is the vortex-type diversion radiator, these fins are molded by die-casting, the heat is more dense, and are tilted in a certain direction to help the passage of air flow, this type of heat sink used in the famous "turbine fan" and the original CPU cooling fan. For this indicator, I suggest that you from the fan profile, fan size, blade design and fan thickness, such as comprehensive inspection, usually different shape of the fan on the impact of cooling will not be too large, but in contrast, the size of the fan to the chip cooling plays a relatively large role.

7. Fan Exhaust Air Volume

Fan exhaust air volume can be said to be a relatively comprehensive indicator, so we can say that exhaust air is the most direct factor in measuring the performance of a fan. If a fan can achieve 5000 rpm, but if the fan blade is flat, it will not form any airflow, so the relationship between the exhaust air cooling fan, fan blade angle is the determining factor. It is easy to test a fan exhaust air volume by placing your hand near the heatsink to feel the intensity of the blown wind, usually a good quality fan, even if we are far away from it.