
The Noctua NF-A14x25 G2 appeared on the market around twelve years after the previous model. The round frame version for air coolers had previously appeared together with the Noctua NH-D15 G2, but the version with the square fan housings is better suited for use as a case fan and is also optimally shaped for use on radiators. In the Noctua NF-A14x25 G2 test, we take a look at whether the long development time was worth it and for whom the purchase of the rather expensive fans is worthwhile.
Versions and specifications
- Single packs / double packs
- Low-speed version
- Round frame versions
At the time of testing, there are three versions of the Noctua NF-A14x25 G2 PWM. Firstly, this model as a regular version. Then there is the LS-PWM version, where LS stands for Low Speed, as the successor to the ULN version of the original Noctua NF-A14. Last but not least, there is the push-pull twin pack with slightly different speeds for the two fans, similar to the set on the NH-D15 G2.
Size | 140 x 140 x 25 mm |
Fan speed | 1500 RPM (standard) 800 RPM (LS) 1475 & 1525 RPM (PP double pack) |
Cable length | 20 cm (30 cm extension cable supplied) |
Material | Sterrox Liquid Crystal Polymer (LCP) |
Noise level | max. 24.8 dB(A) (standard / PP) max. 11.4 dB(A) (LS) |
max. static pressure | 2.56 mm H₂O (standard / PP) 0.71 mm H₂O (LS) |
Max. air flow | 155.6 m³/h (standard / PP) 81.6 m³/h (LS) |
Max. power consumption | 2.28 W (standard / PP) 0.48 W (LS) |
Expected service life | 150,000+ hours (more than 17 years continuous running time) |
Guarantee | 6 years warranty |
Price | € 39.90 * (single pack, standard) € 39.90 * (single pack, LS) € 76.90 * (double pack, push-pull) € 39.99 * (single pack, round frame version for air cooler) € 76.90 * (double pack, round frame version for air cooler) |
Development history
- Long development time due to detail improvements and quality control
- First prototype could already be seen in 2018
Most manufacturers keep their developments secret until they are released. Not so Noctua, who willingly disclose many steps of the development process with confidence, allowing a complete history of the development.
Noctua launched the original NF-A14 back in 2012. These were the reference for 140mm fans for years, but the competition had plenty of time to catch up. Especially since the release of the impressive Noctua NF-A12x25 in 2018, customers in the high-end fan market have been hoofing it and waiting for the new generation in the 140 mm segment. Noctua had already presented the first prototype at Computex 2018, which looked very similar to the Noctua NF-A12x25 at the time. These concepts have already inspired other brands, such as the very solidly performing Thermaltake Toughfan Pro.
However, Noctua was not yet 100% satisfied and worked in particular on the sound of the pull configuration and presented some drastically changed designs of the prototypes in the coming years. In addition, the distance between the fan blades and the frame was to be reduced as much as possible for the best possible performance and the lowest possible pressure loss. Noctua has also carried out intensive tests to ensure quality and durability. This also involves improvements to details and further test runs.
Now twelve years on, the Noctua NF-A14x25 G2 have appeared on the market and, similar to the Noctua NF-A12x25, aim to shake up the fan market this time in the 140 mm range. Spoiler: A new 120 mm prototype with visible development progress of the 140 mm version tested here was already shown at Computex 2024.
Packaging and scope of delivery
- New packaging design
- No plastic packaging as far as possible
- Extensive range of accessories included: Y-splitter, low-noise adapter, extension cable, silicone mounting brackets, fan screws and silicone interchangeable corners
At first glance, it is noticeable that the packaging corresponds to the new design. This means that the white areas are gone and the product is clearly illustrated. There are also no more hangers for stores. This presumably saves space. Instead of the flap that can be opened from the outside of previous packaging, it is now designed a little more efficiently and completely dispenses with plastic trays on the inside. To ensure that the Noctua NF-A14x25 G2 is still well protected during transportation, the box is folded in such a way that it offers two layers of protection. The technical information that could previously be found on the inside of a flap is now on the inside.
Apart from the fans, an extensive accessory package is also supplied. This consists of the following:
- a Y-splitter for attaching several fans to one header
- a 30 cm long PWM extension cable per fan
- one low-noise adapter per fan (the powerful NA-RC16 for the regular models and the narrower NA-RC8 for the LS model)
- fan screws
- Silicone brackets for mounting as a housing fan
- Replacement silicone corners if you want to replace the factory-fitted sealing lip
There is also a protective strip of paper between the fan blades and the frame. This protective strip must of course also be removed before commissioning.
Design
- Typical Noctua beige-brown color scheme
- Strongly curved fan blades
At the time of testing, only the beige-brown version of the Noctua NF-A14x25 G2 is available, but it has already been announced that a black version is also in development. So far, however, the choice remains whether you like Noctua’s brown design or not. For example, with regard to the trend towards housings with wooden components: Here I find brown fans suitable. Otherwise, it will be difficult to combine brown Noctua fans with models from other brands in a visually harmonious way. Particularly with regard to the price, it can make sense to use Noctua fans in critical areas (e.g. on radiators), but to use cheaper case fans in the main. This would be easier to achieve in a visually harmonious way with black Noctua fans.
Back to the test of the Noctua NF-A14x25 G2: What is striking about these fans is the strong curvature of the fan blades. In contrast to the Noctua NF-A12x25, there is no longer an exposed piece of metal in the middle that could tarnish over time. A pity really – I liked the look of it. What also stands out are the indentations at the corners of the new fans. At first glance, it looks as if something is missing. I can’t explain this with certainty, at best I can speculate about frame stability. I had already noticed similar indentations on the competition, the Thermaltake Toughfan EX14 Pro.
Apart from that, all standard dimensions of regular 140 mm fans are adhered to. Of course, you won’t find RGB – no loss of performance is risked for lighting.
Build quality
- High build quality
- Impressively small distance between the fan blades and the frame
- Very torsion-resistant frame
- Improved cable sheathing
In this price range, the Noctua NF-A14x25 G2 test must of course also take a look at the build quality. With the demands of the high premium segment, a fan must not show any significant weaknesses. However, this has always been one of the areas in which Noctua has been able to score points and is now also one of the brand’s strong points. The processing tolerances are extremely low. The distance from the fan blades to the frame is impressive and one of the most important aspects of the fan. This also means that the frame must be very torsionally rigid so that the fan blades do not hit the frame even when installed. This has also been achieved. All parts are also neatly finished and there are no sharp edges or anything similar.
The cable itself is kept relatively short, which, depending on the installation position, ensures that you don’t have to store too much superfluous cable anywhere in the housing. If you need a longer cable, you can use the extension cable supplied. The sheathing of the cable gives it a very high-quality appearance and protects it well against damage from sharp edges. The sheathing appears somewhat thicker than on the NF-A12x25, for example. And the kinks no longer seem to be as clearly visible as they were on previous fans. Ergo an improvement here too.
And even when turning on the fans by hand, no motor noise is perceptible – even at close proximity to the ear. I have experienced this differently – even with Noctua fans.
All in all, there is no problem with the fans here either. The workmanship of the Noctua NF-A14x25 G2 is therefore, as expected, in the absolute top range.
Comparison with the predecessor model
- The differences to the previous model are clear
- There are also slight shifts in the color
The Noctua NF-A14x25 G2 is quite a bit more expensive than the previous NF-A14, which is still available. This may raise the question of where the differences actually lie. However, at a second glance at the latest, the question arises as to where the similarities are apart from the color. And even the colors are slightly different; the beige tone of the G2 has become a touch lighter and the fan blades appear slightly less saturated brown due to the liquid crystal polymer. The frame of the newer fans has become stronger in favor of torsional rigidity, whereas that of the older model was robust but noticeably narrower.
Instead of seven fan blades, the new generation has nine, which are significantly narrower towards the middle – but have a much stronger curve overall and are more tapered than the older models. These had even larger, wider fan blades, which today are almost inconspicuously shaped. The cable sheathing has also become stronger and no longer emphasizes kinks as much. In short: the difference is very clear to see.
Noctua accessories
- Corners can be changed
- Noctua offers optional accessories such as spacers
- Quick, screw-free installation is possible
On the one hand, Noctua always shines with a wide range of accessories included in the scope of delivery, on the other hand, Noctua offers additional optional accessories. What was usually an optional accessory for most other fans is the sealing lip for the radiator insert. This is not only included with the Noctua NF-A14x25 G2, but is already fitted ex works. And in a specially adapted version with pressure-reducing corners. If you want to replace these with the “normal” corners, for example to better match other Noctua fans that you are already using, these are also included. The silicone parts can simply be removed and replaced using a system with holes and plugs. When changing back to the sealing lip, you just have to make sure that there is a cut-out for the cable on one side.
Not included in the scope of delivery, but optionally available, Noctua offers the NA-IS1-14 spacer, which ensures that the fan does not pull its fan blades directly past surfaces in pull configurations. This additional spacer therefore already reduces the noise level. In addition, the otherwise almost completely covered space above the fan motor and at the corners becomes a little more accessible. This may therefore allow air to be drawn in over a larger area, which can improve performance. Disadvantage: You pay extra here, of course.
Also included are silicone brackets that can be used instead of the fan screws when used as a case fan. These have the advantage that it is quicker and easier to position the fans, that the holes in the fans are not damaged by the thread-cutting screws and that the fans are directly protected against vibration.
Different versions
- Standard PWM version for all applications
- Low-speed (LS) as a particularly quiet housing fan
- PP double pack for push-pull scenarios, such as on radiators
There are currently four versions of the fan. The regular version is the Noctua NF-A14x25 G2 PWM as a standard fan with a maximum speed of 1500 RPM and speed control via pulse width modulation (PWM), which is the standard nowadays. This version is a particularly good choice for radiators or for housings with few fan slots, where it is preferable to use faster fans rather than many.
As a case fan in larger cases, the Noctua NF-A14x25 G2 LS PWM version limited to 800 RPM will be optimal in most cases. This low-speed version achieves the most balanced noise performance speed of 800 RPM for 140 mm fans, but is not accelerated beyond this by automatic features. This ensures a particularly low noise level. This version is simply always quiet.
Finally, there is the double pack in the push-pull version. This includes the Noctua NF-A14x25 G2 PWM PPA and PPB. The PPA fan aims for a maximum speed of 1475 RPM and the PPB fan 1525 RPM. This means that both are still within the tolerance range of the regular fan, but the minimal variance in speed ensures that the effect of the beat is reduced – a rhythmic humming that is clearly perceptible when two fans of almost the same speed are working in succession. This happens, for example, with coolers with two fans in series or with radiators with a push-pull fan configuration.
Ultimately, however, the twin pack with the fans is simply a touch cheaper and you can also use the fans side by side like the regular PWM version.
Last but not least, there are special versions for air coolers – the round frame versions.
View of the round frame version
- A round frame fan is usually required for use on air coolers
- 140 mm round frame fans have the hole spacing of a regular 120 mm fan
Having tested the Noctua NH-D15 G2, I already had contact with the round frame version of the Noctua NF-A14x25 G2. In terms of specifications, there are no significant differences. The frame is simply designed differently to allow a 140 mm fan to be built with the hole spacing of a 120 mm fan, which is required for most air coolers. There are only a few 140 mm air coolers that use 140 mm fans in the standard format. So if you want to give older air coolers a new lease of life with fresh fans, this is probably the version you need.
The round frame versions can also be found in a standard single pack variant and a dual pack push-pull configuration with slightly offset speeds to reduce noise from the levitation.
Apart from that, using the Noctua NF-A14x25 G2 with the standard frame from this test is better for most other applications if the round frame version can also be mounted as a case fan under certain circumstances.
Noctua NF-A14x25 G2 – expensive fun
- Very high price: Make sure that the core components are not neglected by investing in fans!
- Aimed at users of high-end hardware
- High durability puts the high price into perspective
One point that cannot be ignored is the high price of the Noctua NF-A14x25 G2. Of course: Noctua has always been known for its high prices and the quality that goes with them. But where the predecessor models were already not cheap, here you pay a surcharge of almost 50%. Fully equipping a computer can therefore quickly become very expensive, depending on the size of the case. You should therefore be aware that these fans are a kind of halo product. So even if they are the best 140 mm fans on the market in terms of performance, I only recommend them to those who already use the best of the best from the world of hardware. Otherwise, in most cases it will make more sense to use a set of cheaper fans and invest the money saved in more powerful basic hardware that actually delivers better performance.
Or to put it another way: the target group is users of high-end hardware who are aiming for that last bit of extra premium.
Apart from that, the price is understandable: years of work have gone into the development of the Noctua NF-A14x25 G2 and a great deal of development and fine-tuning. Accordingly, a certain price point is understandable even without considering the top performance and the high quality of workmanship. Previous fans have also proven to be extremely durable. For example, I privately use Noctua fans from 2010, which still work like new and look the same if you regularly remove the dust. It is therefore to be expected that Noctua fans purchased now also have the potential to outlast several generations of hardware components. So the investment may be hefty in the short term, but can be put into perspective in the long term.
Test setup
- Test as a housing fan and on radiators
- Different scenarios: Same speed, low volume, maximum power
Tests are carried out in two systems. The test as a case fan is carried out in a Corsair 6500D Airflow with one fan in the front in the lowest possible position and one fan in the rear. A continuous loop of 3DMark Firestrike is used to expose the processor and graphics card to a constant continuous load. The graphics card fan is set to a constant speed so as not to be influenced by automatic functions. The fanless Noctua NH-P1 is used as the processor cooler.
The test as a radiator fan is carried out on the rather powerful radiator of an Arctic Liquid Freezer II 280, which sits in the front of a Fractal Design Pop XL Air. The fans are installed in pull configuration to additionally test the effect of the optional Noctua NA-IS1-14 accessory. An overclocked Intel Core i5-9600K is used as the processor, which draws a power of 115W under Cinebench load.
For the Noctua NF-A14x25 G2 test, the four fans are each tested in three realistic settings: at a volume at the audible limit, at a fixed 800 RPM (which is also the maximum speed of the LS version), and at maximum power. The 800 RPM was chosen because it often represents a good compromise between low noise and high performance.
In addition to the Noctua NF-A14x25 G2, the original NF-A14, the be quiet! Silent Wings Pro 4 and the Thermaltake Toughfan EX14 Pro, which stylistically correspond to an earlier development stage of the NF-A14x25 G2, are compared.
The fans from be quiet! and Thermaltake have the advantage and disadvantage that they have a higher maximum speed. This is an advantage because it influences the maximum performance and gives more flexibility in the settings. The disadvantage is that they can become louder if they are not set correctly. The fans from be quiet! can be limited by switches on the back – without external low-noise adapters.
Note on the test results
- Explanation of the volume measurement
- Graphics card clocked down relatively quickly
In the case of volume, a dash means that the difference between the volume and the surroundings was no longer measurable (30dB(A) and less). For the temperature, the delta is specified, i.e. the difference between the measured temperature and the room temperature, in order to eliminate fluctuations in the room temperature. So if the specified delta is 40 Kelvin and the room temperature was 22°C, then the measured processor temperature would have been 62°C.
Perhaps I should have set the graphics card fan higher in the case fan test to prevent it from throttling too quickly (“throttling”), but then the volume measurement would have been falsified.
When testing the Noctua NF-A14x25 G2, the push-pull double pack was used with the PPA and PPB fans sitting next to each other on the radiator. In the case fan test, the slightly faster PPB fan was placed in the front behind the dust filter and the PPA on the rear of the case.
Test as case fan
- The Noctua NF-A14x25 G2 are the most efficient premium case fans
- The be quiet! Silent Wings Pro 4 are not far behind
Fan | Temperature delta in K |
Speed in RPM |
Noise level in dB(A) |
Noctua NF-A14x25 G2 100% |
CPU: 47.2 GPU: 45.4 |
1500 | 46,6 |
800 RPM | CPU: 54.3 GPU: 45.5 |
800 | 31 |
Audibility limit | CPU: 55.8 GPU: Throttling |
750 | / |
Noctua NF-A14 100% |
CPU: 49.5 GPU: 45.8 |
1480 | 47,6 |
800 RPM | CPU: 56.9 GPU: 48 |
800 | 32 |
Audibility limit | CPU: 58.5 GPU: Throttling |
710 | / |
Thermaltake Toughfan EX14 Pro 100% |
CPU: 45.5 GPU: 47.6 |
1970 | 53,8 |
800 RPM | CPU: 56 GPU: Throttling |
800 | / |
Audibility limit | CPU: 56 GPU: Throttling |
800 | / |
be quiet! Silent Wings Pro 4 100% |
CPU: 44.9 GPU: 43.4 |
2170 | 52,8 |
800 RPM | CPU: 56.5 GPU: Throttling |
800 | / |
Audibility limit | CPU: 55.2 GPU: Throttling |
900 | / |
Impressive. The Noctua NF-A14x25 G2 proved to be very effective in the test. The volume is lower than on the predecessors and overall the maximum volume was the lowest. Nevertheless, the performance is more powerful. The Thermaltake and be quiet! fans fight their way to the front at full power due to the higher possible speed, but otherwise the Noctua NF-A14x25 G2 performs best. The be quiet! Silent Wings Pro 4 follow close behind – these are the quietest if you take the speed as a reference, but also need a little more speed to deliver the performance.
Test as radiator fan
- Noctua NF-A14x25 G2 are significantly quieter than other fans with comparable maximum performance
- Noticeably more power than the other fans at a lower noise level
- Noctua NA-IS1-14 has an impact, but it’s not huge
Fan | Temperature delta in K |
Speed in RPM |
Noise level in dB(A) |
Noctua NF-A14x25 G2 100% |
40 | 1500 | 47,4 |
800 RPM | 43 | 800 | / |
Audibility limit | 42 | 820 | / |
Noctua NF-A14x25 G2 + NA-IS1-14 100% |
39 | 1500 | 46,6 |
800 RPM | 42 | 800 | 31 |
Audibility limit | 42 | 780 | / |
Noctua NF-A14 100% |
41 | 1500 | 50,5 |
800 RPM | 44 | 800 | 33 |
Audibility limit | 45 | 700 | / |
Thermaltake Toughfan EX14 Pro 100% |
39 | 1970 | 54,5 |
800 RPM | 44 | 800 | 31 |
Audibility limit | 45 | 760 | / |
be quiet! Silent Wings Pro 4 100% |
40 | 2130 | 52,3 |
800 RPM | 45 | 800 | / |
Audibility limit | 43 | 930 | / |
Here too: Impressive – and even more than as a case fan. In the test, the Noctua NF-A14x25 G2 proved to be outstanding in the low-noise range, clearly beating the entire competition. At maximum performance, the be quiet! Silent Wings Pro 4 are roughly equal and the Thermaltake Toughfan EX14 Pro is even ahead – but they are much louder. The original Noctua NF-A14 is not so far behind in this test, but is still at the bottom.
And what does the NA-IS1-14 spacer do? At maximum speed, it has reduced the fan noise a little and the performance has increased minimally – but this is well within the measurement tolerance. Interestingly, the volume actually increased slightly at lower speeds in my setup – but ultimately the difference was not huge.
The differences still seem small here – however, the difference will be more noticeable with a higher heat load due to more power-hungry, hotter processors.
Conclusion
The Noctua NF-A14x25 G2 fans are convincing in the test and are at the top of the performance/volume ratio. Of course, the price is high and so are the expectations in terms of performance. But even if I put the best 140 mm fans to date up against the Noctua newcomers here: The NF-A14x25 G2 pull ahead in terms of performance and remain quieter. Added to this are the Noctua reliability, the extensive accessories package and the robust workmanship, which also outperforms older Noctua fans.
On the other hand, other brands now offer a few quality-of-life features, such as the multi-stage integrated low-noise adapter with switch in the be quiet! Silent Wings Pro 4 or the cable-saving daisy-chaining of the Thermaltakt Toughfan EX14 Pro. Instead, the Noctua NF-A14x25 G2 are simply very good fans without such “gimmicks”.
If you don’t care about such special functions and can get by with the color design of Noctua fans, you will find extremely impressive 140 mm fans in the Noctua NF-A14x25 G2 – albeit for the higher price. After the NF-A14 predecessors, which were slowly showing their age and only played in the “midfield of premium fans”, the new generation is back at the top of the performance range.
Noctua NF-A14x25 G2
Performance
Volume
Equipment
Processing
Price-performance ratio
96/100
The Noctua NF-A14x25 G2 are very impressive 140 mm fans. They are not cheap, but that is not to be expected from the top performance.