Very few high performance 120mm fans can simultaneously achieve the coveted trinity of airflow, static pressure and low noise output. Of course, this equilibrium is subjective depending on context but usually there will be some sort of a drawback the more you pursue one side of the triangle.

Build quality is implied from the get-go and this specific sector for a long time has been dominated by Noctua, with their NF-A12x25 PWM fans, that have so far, in our opinion, the best overall balance. There have been small exceptions like Phanteks with their T30 series, but these don’t respect the standard 25mm thick format.

Enter be quiet! who has developed their new Silent Wings Pro 4, which promise to raise the stakes even further. With stats like a 3000 RPM 6-pole 3-mode fluid-dynamic bearing which is rated for 300,000 of continuous operation (over 34 years!), 5 years warranty, modular frame, up to 5.31 mm H2O of static pressure, well, this fan looks to be the endgame for any scenario.


Be Quiet! is a premium brand manufacturer of power supplies and cooling solutions for your desktop PC. With numerous awards under their belt and considered the best German power supply manufacturer from Germany since 2006 – was awarded nine times in a row as “Manufacturer of the Year” in the power supply category by the readers of the well-known German hardware magazine PC Games Hardware. In the category “fans”, be quiet! earned the first rank for five consecutive times and belongs to the Top 3 CPU cooler brands for more than three years in a row. The community of Hardwareluxx also voted be quiet! as “Manufacturer of the Year” in the PSU category for four consecutive years.


Prices and Availability


This new Silent Wings 4 series from be quiet! is available in both 120 and 140mm formats with plenty of variations (3 sub models each). Only the ‘Pro’ ones provide the ultimate performance.

Thus the 120mm retail for $31, which is basically the same as Noctua A12x25 and Phanteks T30. Worth pointing out that, technically, the Noctua Industrial NF-F12 iPPC 3000 RPM should be here as one of the test subjects.

Alas, we are mentioning the Noctua A12x25 as one of the main competitors (which despite their max 2000 RPM vs 3000 RPM like the be quiet! and Phanteks), because they are the benchmark for noise output and overall balance.


Presentation and Specifications


* Courtesy of their website.

Silent Wings Pro 4 120mm PWM is the most progressive, performant and versatile fan by be quiet!

* Optimized fan blades for the highest performance on radiators and heat sinks
* Speed switch allows changing maximum PWM speed between medium-speed, high-speed and ultra-high-speed (up to 3000 rpm)
* Small tip clearance and a fan frame with a funnel-shaped air outlet for extremely high air pressure
* Virtually inaudible operation at regular speed
* 6-pole fan motor and fluid-dynamic bearing for less vibration and very smooth operations
* Individual mounting systems for use as a case fan or with a radiator
* 5-year manufacturer warranty


Visual Inspection


The Silent Wings Pro 4 fans come shipped in a sturdy all black box with excellent branding and highly impressive specs.

The perfectionist approach regarding presentation continues inside the packaging where we see both the fan and the accessories having their own box. Furthermore, the main highlights of the fan are detailed on the top cover.

An impressive feature of these fans is the modular nature regarding the corners of the frame. You get 3 sets, each one optimised for key areas such as radiator cooling, case or maximum vibration reduction.

These fans are an evolution of the previous Silent Wings 3 generation from be quiet! but they still preserved some important and signature elements like the ribbed blade design and overall sleek looking frame. But this new ‘Pro’ line-up has been developed to the maximum.

A quick visual cue is the logo from the front of the fan is now also black, thus making these a true stealth build option. Then the tolerances have been tinkered as in the blades are now even closer to the frame.

The claimed specs for these fans are quite impressive. The ‘Pro’ ones are rated up to 3000 RPM (!), pushing up to 142.5 m3/h of airflow, with a static pressure of 5.31 mmH2O while not going over a claimed 36.9 dB(A) of sound output. All of these are achieved thanks to the 9-ribbed blades and the 6-pole 3-phase fluid dynamic bearing rotor that is rated for extreme long life operation, of 300,000 hours of continuous operation! (over 34 years!).

Another key feature of these new fans is the 3-phase selection of speed options that basically hard-sets the maximum operational speed. Just make sure you select the desired level before installing the fan because no way to access it afterwards.

M = medium speed, 1600 RPM
HS = High Speed, 2500 RPM
UHS = Ultra High Speed, 3000 RPM

be quiet! even went the extra mile to customize the 4-pin PWM port with a custom mount. The fully braided cables is 50 cm long so it will have plenty of reach.

Now let’s explore the detachable corners system. be quiet! doesn’t show anywhere how to remove them but basically you just have to press on the two protruding tabs to release the corners. Also they are one sided so you can’t install anything the wrong way.

The pre-installed ones are apparently optimised for radiator cooling since they block the air from escaping through the frame.

The other two are optimised for case and max vibration reduction and that’s why they are visibly trimmed down in size. Also the installation method will different but at least be quiet! is giving you plenty of options.

Choosing different corners will also modify the overall look of the fan.

Mother nature gave a quick preview in airflow with a windy day but now let’s head back inside and properly test them.

As per the upcoming testing routine, they will be tested on a 240m AIO against some other high performing 120mm fans.

Luckily, the testing AIO has a fan splitter that is capable of handling the rated power consumption for the be quiet! Silent Wings Pro 4 fans since its own fans use more Watts and Amps.

The Silent Wings Pro 4 fans will match perfectly in an all black/stealth build.


Testing methodology


  • The be quiet! fans will be placed on the Alpenföhn Glacier Water High Speed “der8auer” 240mm AIO radiator and then compared in turn to the to the stock fans of the same liquid cooler – Alpenföhn Wing Boost 3 ARGB High Speed – and a main competitor in this sector, the famous Noctua NF-A12x25 PWM, all of which at various key RPM points
  • The Ryzen 5 5600x will be tested at 4.0 GHz @ 1.05v as the baseline parameter since in stock form, the results are highly inconsistent due to the board’s BIOS pumping inconsistent voltage values. Furthermore, the CPU will be tested at its stock settings and then Oc’ed at 4.7 GHz for 1.275v
  • As the main torture test, we will employ a 2 minute run in AIDA64
  • Room temperature was recorded at ~18°C
  • For the noise testing, we used our Pyle PSPL01 placed 50 cm away from the setup, and all of the fans will be tested at various RPM points, with a CFM to d(BA) ratio
  • Thermal paste used Noctua NH-H2
  • Any results over 90°C in any condition are considered a fail

Hardware used:

CPU: AMD Ryzen 5 5600x
CPU Cooling: Alpenföhn Glacier Water High Speed
“der8auer” 240 mm AIO RGB

RAM: 16GB Team Group T-Force Night Hawk RGB 3000 MHz CL16
Motherboard: ASUS ROG STRIX B550-i Gaming mITX @ BIOS 2803
Boot SSD: Samsung 970 PRO 1TB M.2 Gen3x4 MLC PCIe NVMe 1.3
Video card: ASUS GTX 1080 STRIX A8G
PSU: Corsair SF750 SFX Platinum
Case: Phanteks Evolv Shift XT ARGB mITX
Competition Fans: Noctua NF-A12x25 PWM & Alpenföhn Wing Boost 3 ARGB High Speed


OS: Windows 10 Pro x64 Version 22H2
NVIDIA Drivers528.49
CPU-Z v1.95To verify the CPU’s and RAM’s statistics
Core Temp v1.17 – To see the temperatures in real time
AIDA64 Extreme v6.60Memory analysis and Benchmark suite
MSI Afterburner v4.62 – To record the FPS and load/temperatures
3D/Game(s)Assassin’s Creed Valhalla with latest update, set at 1080p, ultra quality settings, no V-Sync


Testing, Results and Analysis


Considering the level of variables, we will test separately the be quiet! Silent Wings Pro 4 fans through their RPM range and then against the competition but at similar speed points.

Thus, from top to bottom we have the ‘basis’ scenario (CPU is at 4.0 GHz for 1.050v), the CPU in stock form and the OC scenario (4.7 GHz at 1.275v). Then from left to right we have the Silent Wings Pro 4 fans at 50% RPM, 80% RPM and 100% RPM.

Now let’s test them against some other fans. It’s quite impressive to see that the Silent Wings Pro 4, even at 1000 RPM (which is barely 33% of its total RPM range) almost matches what the competition does at their 50% RPM point. (Noctua A12x25 PWM’s max RPM is 2000 RPM while the Alpenföhn Wing Boost 3 ARGB High Speed will spin up to 2200 RPM)

Then at 1500 RPM (50% for the Silent Wings Pro 4s, 75% for the Noctua A12x25 and 68% for the Wing Boost 3s), the be quiet! fans start to take the lead.

At 2000 RPM the Noctua tops out while the Wing Boost 3s still have 200 RPM to go. The Silent Wings Pro 4s will keep on smiling since they are at 67% of their top RPM potential.

Finally, with all of the fans at their max potential RPM speed, in a comparison test which is obviously biased towards the be quiet! Silent Wings Pro 4s but still offers a another interesting perspective, to see how much you would gain with these fans at 3000 RPM.

After all of those torture tests, a gaming session is a walk in the park for these fans, especially that they will operate near to complete silence while providing excellent cooling. Here everything was set on auto RPM for both the AIO, fans and GPU.

The final test is the noise output. Here are the Silent Wings Pro 4 fans going from 30% (900 RPM), 50% (1500 RPM), 80% (2400 RPM) and 100% RPM (3000 RPM) points.

But we need a different type of chart here to understand their true value regarding performance to noise output. Basically the Silent Wings Pro 4 can move more air while being as quiet or even quieter than the Noctua across the measured RPM range.




be quiet! has created basically the equivalent of the ‘Swiss Army Knife’ in the 120mm fans category. These Silent Wings Pro 4 can cover a wide variety of scenarios and furthermore, they excel at all of those. The fact that they encompass so many attributes from build quality, noise output, features and very high performance figures, make these the best 120mm fans on the market right now. Of course, other models will be quieter or even more powerful, but none manage to get such an incredible sweet-spot out of the box!

The good:

+ So far, the best 120mm x 25mm fans out there
+ Incredible performance to noise output ratio across the RPM range
+ Epic build quality
+ Ridiculous continuous operation endurance rating
+ Modular corners
+ Perfect for an all blacked out / fully stealth build
+ User selection for 3 RPM thresholds modes

The bad:

– Make sure you select the desired mode before you install them in your case or AIO, because you can’t access the slider without removing the fan


Glob3trotters “Editor’s Choice” Award 5 out of 5

Many thanks to be quiet! for supplying us with these epic items!


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