Page 2 - Physical Look - Hardware
The be quiet! Silent Wings 4 goes back to the basics offering zero RGB lighting options in this entire lineup of fans. be quiet! keeps this fan simple and to the point. The entire fan is black in color. Likewise to many other fans, the be quiet! Silent Wings 4 has a bit of branding on the middle of the impeller. On the edges, you have the choice of two fittings, which both have rubber around the holes. This rubber offers better sound dampening for the fan. This fan design is quite unique as we here at APH Networks have never seen the option of mounting fittings on a fan. We will expand on this design shortly. Overall, the design of this fan is quite understated compared to all the RGB products in the market today.
Internally, the fan uses fluid dynamic bearings. These bearings are similar to regular fluid bearings, except they use the movement of the parts themselves to draw the liquid into the bearing. The uses of fluid dynamic bearings increases the longevity and consistency of the fan while also lowering the noise produced compared to other types of bearings. The one negative to this type of bearing is the same as all fluid bearings, as they must maintain pressure to prevent wear and mounting orientation consideration may be required. The mounting position may be a moot point as these fans are rated for 300,000 hours; being plentiful for any fan. We will see how much noise this fan outputs when we test them later.
Taking a closer look at the fan blades, you can see some notable difference compared to other fans. If you look at the fan blades, you can notice a texture utilized to allow for slightly better airflow. There is a small gap in between each of the fins, having no overlapping ones. The angle each blade sits in comparison to the rotating middle is about 45 degrees. The curvature of the blades is about average. There is a total of nine blades on the impeller. It is important to note that the impeller on this fan is quite large. We will see how this large impeller affects the airflow during our performance tests.
Now, let us take a look at the exciting innovation before our eyes, the mounting fittings. According to the instructions, we have two options, the hard plastic fittings and anti-vibration fittings. Personally, I would always go for the anti-vibration fittings, as they will typically reduce any unwanted additional noise from the fan. The intent is for the anti-vibration fittings to be used for regular mounting and the plastic fittings to be used on radiators. Both of these fittings use the same mounting system, having a buckle reminiscent of a bicycle helmet. Structurally, this mechanism is quite secure and will not generate any noise from the friction of these parts. Despite not finding much use for this feature, I personally am a fan of it, pun intended. I can see the many possibilities of better fan mounting options built for specific purposes.
On the output side, four arms hold the fan in a typical manner as seen in the image above. These arms will obstruct minimal air from passing through. There is a single cable on the be quiet! Silent Wings 4 attached to the fan for power and fan control. The cable is a 4-pin PWM controlled header that is approximately 470mm in length. This should be long enough to maneuver around most cases for a clean build, as this is a single fan with a simple setup. The cable is quite flexible, and braided for better durability.
Looking at the specifications, we can see the maximum CFM or cubic feet per minute rating of the be quiet! Silent Wings 4 is 76.7 CFM. This is quite high for a 120 mm fan. Air pressure is another important metric to evaluate the performance of a fan. In scenarios where there is a mesh or heatsink that obstructs airflow, the fan is required to have the strength to pump air through it. This strength is measured in mmH20. The be quiet! Silent Wings 4 specifies 3.96 mmH2O maximum. Note these values are achieved by the fan spinning at about 2500 RPM, which is the fan’s maximum speed. Another important aspect of fans is their noise level, which is measured using dB, or decibels. The specifications do not state a minimum noise level, but specifies a maximum noise level of 31.2 dB. Taking this into account, these fans can be considered to be low in noise level when considering their high RPM and airflow.
Page Index
1. Introduction, Packaging, Specifications
2. Physical Look - Hardware
3. Performance Tests
4. Conclusion