Noctua NF-S12B FLX 120mm Fan

Aug 12th, 2009 | By

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Noctua NF-S12B FLX 120mm Fan

: 08/12/09 – 08:10:30 AM


: Cooling

Page 1 : Introduction


Noctua is known for their high quality cooling products such as fans, heatsinks, and thermal compounds. I have reviewed several of their products in the past and have always been impressed by the Austrian company's ‘sound-optimized premium components.’


In this review, we'll be looking at Noctua's
120mm fan featuring Noctua's latest modified blade geometry. This is an update of the NF-S12 fan that Anthony reviewed almost three years ago.

Noctua NF-S12B

Page 2 : Package

Noctua's usual brown and blue color scheme is immediately apparent upon looking at the package that the NF-S12B comes in. A clear window allows us a peek at the beige fan with its brown beveled blade tips. We can also see one of the four rubber mounting posts.

Noctua NF-S12B

As we know already, the fan is designed in Austria.

Noctua NF-S12B

One side of the package describes this version of the NF-S12B, the FLX, which has 1200, 900, and 600 RPM settings. The other side describes two other fans – the NF-P12 which I reviewed earlier and the NF-S12B ULN which provides 700 and 500 RPM functioning.

Noctua NF-S12B

The back has a description of the fan in seven languages, an overview of some unique features, specifications, and a list of contents.

Noctua NF-S12B

There are some technical explanations hidden underneath the back panel that flips out. Also, there is a diagram showing how to install the fan using the rubber mounting posts and descriptions of the noise-reduction adaptors, which basically undervolts the fan.

Noctua NF-S12B

Let's take a look at the features and specifications.

Page 3 : Features & Specifications

Noctua's website is a valuable resource for everything you want to know about the NF-S12B or any of their other products. You can find features, specifications and technical backgrounds.

Noctua's description is as follows:

Succeeding the vastly successful NF-S12, the NF-S12B is a next generation quiet fan featuring Noctua's advanced SCD2 technology as well as a highly optimized blade geometry with Beveled Blade Tips that improves its award-winning predecessor's airflow efficiency by up to 10%. Topped off with Noctua's time-tested SSO-Bearing, 6 years warranty and versatile 1200/900/600 rpm speed settings, the NF-S12B FLX is a premium quality fan that offers full flexibility in quiet to ultra-quiet case cooling.

The features:

Noctua NF-S12B

Some of Noctua's proprietary engineering makes it into the NF-S12B FLX.

The specifications:

Noctua NF-S12B

Noctua NF-S12B

Using the noise reduction adaptors decreases the fan speed, airflow and noise level. The aptly named low noise and ultra low noise adaptors reduce fan speed from 1200 RPM to 900 RPM and 600 RPM respectively.

Page 4 : Package Contents

Once you open the box, you will find a clear plastic tray that holds all the contents.

Noctua NF-S12B

Other than the fan itself, we have four screws, four vibration-compensating mounts, the low noise adaptor (LNA), the ultra low noise adaptor (ULNA) and finally a 3-pin to 4-pin Molex converter.

Noctua NF-S12B

The fan has a light beige frame with seven brown blades showcasing Noctua's signature color scheme. The wire is sleeved neatly. Looking at the blades, we can see the beveled tips that are supposed to achieve better airflow and static pressure than conventional 120mm fans.

Noctua NF-S12B Noctua NF-S12B

Here is a closer look at the blade tips.

Noctua NF-S12B Noctua NF-S12B

Next is to cover installation.

Page 5 : Installation

If you are reading a review on a fan, you probably know how to install one using screws.

However, I just want to take a moment to point out how to install the Noctua NF-S12B using the vibration compensating rubber mounting posts.

This graphic, courtesy of Noctua, summarizes the process well:

Noctua NF-S12B

First, insert the rubber posts through the mounting holes and pull from the other side.

Noctua NF-S12B

Then, secure the fan by pulling the free end of the mounting posts through the mounting holes in the fan.

Noctua NF-S12B

The fan may feel a bit wobbly but it is actually quite secure as it required a lot of force to remove the posts. I guess this is intentional as it helps minimize vibrations being transferred to the case.

Connect the power, use one of the low noise adaptors if desired, and that's it!

Page 6 : Testing & Performance

Testing will consist of using the Noctua NF-S12B as a case exhaust fan, since it is meant to be used in low-impedance situations, in an Antec P182 case and measuring the case temperature in comparison to an Antec fan and a generic 120mm fan at different speeds (low, medium, high). Since the generic 120mm fan only runs at one speed, only the Antec and Noctua fans can be directly compared at low and medium speeds.

CPU: Intel Core 2 Duo E6300 1.86GHz
Motherboard: Biostar TF7150U-M7
PSU: Antec SmartPower 2.0 SP-400
Memory: Corsair Value DDR2-667 (PC2-5300) 2GB dual channel kit (2x1GB)
Video Card: PNY GeForce 8600GT PCI-E x16
Hard Drive: Hitachi Deskstar T7K250 160GB SATA II 8MB cache
Optical: Samsung DVD±RW
Case: Antec P182
Control Fans: 2x Antec TriCool (1 inlet, 1 exhaust) set to medium

Exhaust fans: Antec TriCool, Generic 120mm, Noctua NF-P12

Temperature measurements were taken under different conditions using Lavalys Everest Home Edition 2.20. Idle measurements were taken with the computer idling at the desktop for 2 hours and no CPU or hard drive intensive programs, such as antivirus software, running. Load temperatures were taken with 3DMark06 running for 2 hours three times and taking the average of the maximum temperatures. In the case of the Antec TriCool and NF-S12B, the fan speeds will be noted where appropriate; the low noise adaptors will be used on the NF-S12B for the medium and low speed tests.

The ambient temperature was 26ºC throughout all the tests.

Noctua NF-S12B

With all the fans set to high, the generic fan takes the lead. This may be because this generic fan has about 93 CFM of airflow at over 2500RPM. I'm not sure what the revolution speed of the generic fan is but it is probably in excess of 2500RPM. The Antec TriCool and Noctua NF-S12B are evenly matched.

Noctua NF-S12B

The medium fan speed tests show the NF-S12B and Antec TriCool neck and neck once again. In fact, the Antec only had a 1ºC advantage in the load temperature measurements.

Noctua NF-S12B

With the fans set to low, the Antec pulls ahead by 2ºC.

Throughout the tests, the Noctua NF-S12B performed well. There wasn't more than a 1 or 2ºC difference in most situations between the fans tested. More than the cooling performance, the Noctua NF-S12B surprised me with its noise level or lack thereof. It was almost silent at the medium and low speeds, unlike the Antec TriCool which still had a noticeable whine at the lowest fan speed setting.

Page 7 : Conclusion

Noctua makes excellent products and the NF-S12B FLX is no different. It is certainly a unique fan in terms of aesthetics, design and engineering. This is especially evident in the attention to detail that Noctua has paid to the fan – for example, the beveled blade tips. Using the included noise-reduction adaptors, you can make the fan run almost silently without compromising performance too much – not that it is loud by any means even at the normal setting.

Also, the overall package is great. You even get rubber mounting hardware to prevent noise from being transferred from the can and amplified by the case. The low-noise and ultra low-noise adaptors are also great – you won't have to modify the fan or undervolt it yourself.

Noctua NF-S12B

If you are looking for a nice 120mm fan for your case, I highly recommend taking a look at the Noctua NF-S12B FLX – you won't be disappointed.



  • Good performance

  • Very quiet
  • Good overall package
  • 6 year warranty


  • Slightly more expensive than an average fan

I'd like to thank Noctua for making this review possible

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