One of the ways to reduce the temperature of motherboards and computer components is to install additional fans. With their help, it is possible to increase the movement of air and, as a result, improve cooling. In this manual, we will tell you how to Connect Extra Fans To Motherboard and install the fans (coolers) in the computer case.

Choosing places for connect extra fans to motherboard
If you are thinking about installing additional fans in the computer case, then first you need to decide on the places where you will install them. To choose the right places, you need to understand how the air flows inside the computer. The fact is that the heated air itself rises to the top of the case under the influence of convection. This effect can be used to improve cooling. If coolers do not resist natural convection, but rather increase its flow, then cooling will be more efficient.
There is a standard cooler installation scheme that takes into account the natural movement of air:
- blower coolers are located on the front, bottom and side walls of the case;
- blowout coolers on the top and rear walls of the case;
With such a fan installation scheme, the natural air flow is not disturbed, and the fans do not disperse hot air along the case, but blow it out. This is shown more clearly in the picture below.
Do not underestimate this fan layout. It has been used for a very long time and has been tested many times. If you decide to move away from it and set the cooling in your own way, then it is possible that you will not only not lower the temperatures, but, on the contrary, increase them. For example, if the fans are placed in the upper part of the case not for blowing out air, but for blowing in, then this will slightly lower the temperature of the processor , but noticeably increase the temperature of the video card, hard drives and chipset. If you want to know how to test motherboard New and used for performance.
Using this diagram, determine where your chassis lacks fans and where you can install them. For example, if only one blower fan is installed in the case, then you can add several for blowing. Usually 2-3 fans are sufficient to provide good cooling.
determine computer fan size

Once you have decided on the size of the fans, you need to choose the correct size. The point is that the size of a cooler affects its performance and the level of noise it produces. The larger the cooler, the more air it can pass through itself per unit of time and the quieter it works. Therefore, it is not worth saving and you should always install the largest coolers that fit into your computer case.
It is important to understand that different cases are designed to accommodate different cooler sizes. Moreover, different installation locations can be designed for different sizes. For example, on the front side of the case, there may be seats with dimensions 140 × 140 mm, and on the back side of the case, 120 × 120 mm, or vice versa. Therefore, before purchasing, you need to change the footprints and determine the size of the coolers you need.
The easiest and most reliable way to measure cooler footprints is to measure between the centers of the mounting holes. By measuring these distances, you can determine the cooler size based on the values below.
Distance between mounting holes and cooler size:
- 32 mm – 40 × 40 mm
- 50 mm – 60 × 60 mm
- 71.5 mm – 80 × 80 mm
- 82.5mm – 92x92mm
- 105 mm – 120 × 120 mm
- 125 mm – 140 × 140 mm
- 154/170 mm – 200 × 200 mm
Different connection option for fan
Also, do not forget that coolers have different connectors for connection and can be connected either to the computer’s motherboard or directly to the power supply.

At the moment, three main connection options are used, these are:
- 3-pin fan connectors;
- 4-pin fan connectors;
- MOLEX;
The 3-pin and 4-pin fan connectors are for connecting to the motherboard, while the MOLEX connector connects to the power supply.
It depends on the connection method whether you can control the fan speed by software (without using reobass). Normal control is available only on coolers with 4-pin connectors. In this case, you can set certain rpm depending on the processor temperature. Some motherboards allow control when connected via 3 pin. Well, connection using MOLEX generally excludes speed control, since power is supplied directly from the power supply unit.
Therefore, it is advisable to study the instructions for the motherboard in order to determine the number of connectors for fans, the number of contacts (3 or 4-pin), as well as the ability to control through a 3-pin connection. If all the connectors on the motherboard are already occupied, then additional coolers can be connected using a fan splitter.
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how to install case fans to motherboard

Directly installing the cooler into the computer case is not difficult. You need to turn off the computer, turn off the power completely, and remove the side cover.
The cooler is installed from the inside of the case, after which it is fixed with 4 screws from the outside. The main thing is not to confuse the side from which the cooler blows out air. To do this, there is usually an arrow on its body that indicates the direction of the air.
After installing the cooler in the computer case, it must be connected to the motherboard (in the case of 3 and 4-pin connectors) or to the computer power supply (in the case of MOLEX). The 3 and 4-pin connectors have special tabs to prevent them from being inserted incorrectly.
This completes the installation of fans into the computer case, you can assemble the case and check.