[Iron plate & seasonal parts] Check the selling points of the fans you need

Among a wide variety of PC parts, there are a lot of products called iron plates and seasons because of their high performance and cost performance. At each Akihabara shop on weekends, it is a target part that is often lined up at a limited quantity special price. Let's introduce such PC parts and check their performance.

There are various products in the PC parts shop. I'm wondering which one to choose.Let's master the iron plate & hot selling of such PC parts

Improve airflow and cooling performance by replacing or adding fans

A fan that can be replaced or added from the standard accessory fan, such as improving the quietness of the PC case, improving the internal airflow, strengthening the cooling of the CPU cooler (radiator), and easily lighting up the PC.

The types are enormous, and different products such as rotation speed, noise level, and fan control method (power connector shape) occupy a corner of the parts shop. Prices range from under 1000 yen to nearly 4000 yen, and some products are cheap, quiet, and have a lot of airflow.

This time, let me tell you about the selling points of such difficult fans. However, I think there are many people who ask, "Where should I look for the specs?" And "What is the fan control method?", So let's review the basic knowledge of the fans first.

Review the basic knowledge of fans

The size of the fan is the basis of the basics. The mainstream of PC cases and CPU coolers are 120mm and 140mm, and the thickness is generally 25mm, but there are also 38mm thick models that realize thin 20mm, ultra-high speed rotation, and large air volume.

The 38mm thick wide works "Hyper Jet" series that appeared in June 2014.Super high speed rotation, large air volume but super explosion

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The next basic knowledge is the fan control method. The shape of the power connector makes it easy to distinguish, and the 3-pin connector is DC controlled. The 4-pin connector becomes the PWM control.

The 3-pin DC control utilizes the fact that the rotation slows down when the supply voltage is lowered.Therefore, if the voltage falls below the minimum voltage required for rotation, the fan will stop, and the minimum rotation speed will be higher.

PWM control controls the number of revolutions by modulating the pulse signal while keeping the supply voltage as it is. The rotation control can be performed more widely than the DC control, and the rotation speed can be finely controlled according to the temperature from the UEFI and tools of the motherboard.

The only difference between the 4-pin and 3-pin connectors is the presence or absence of a pulse signal, so it is possible to use 4-pin → 3-pin and 3-pin → 4-pin. However, when connecting from 3 pin to 4 pin, if the connector does not support DC control, rotation control cannot be performed and it is necessary to switch the control mode from UEFI. In addition, when the PWM fan is DC controlled, the rotation speed adjustment range may differ from that during PWM control.

DC control 3-pin connector (left) and PWM control 4-pin connector (right).The difference is the presence or absence of a pulse signal

Although it is rare these days, the fan attached to the PC case may have a peripheral shape in which the power connector cannot control the rotation speed.

An increasing number of motherboards are adopting PWM control 4-pin connectors for case fans as well.

On ASUS motherboards, you can switch between DC and PWM controls with UEFI

In addition to the basic values, "static pressure" is important for water cooling.

Finally, let's explain the specs to check when choosing a fan. However, read the number of revolutions, air volume, and noise level.

It should be remembered that the higher the number of revolutions, the higher the air volume, but the noise level tends to increase proportionally, and the air volume is described in either CFM or m ³ / h. 1CFM = 1.7m ³ / h. To convert from m ³ / h to mainstream CFM, it can be converted by "m ³ / h ÷ 1.7 = CFM".

I think it's static pressure that I'm not used to hearing, but this is the power that fans send out the wind. There are many products that do not have a static pressure, but it is an important value when using it for a water-cooled radiator. Especially in a radiator with fine fins and high resistance, the static pressure has a greater effect than the air volume, and even if the air volume is large, if the static pressure is low, the air escape will be poor and the cooling performance may deteriorate.

Some custom water-cooled radiators are 60mm thick, so static pressure is important.