Endorfy Stratus 140 PWM: Low price, high efficiency

Cooling, Extra tests, Fans | | Ľubomír Samák

Endorfy Stratus 140 PWM in detail

The cheapest 140mm fan we’ve tested so far beats even significantly more expensive 120mm models at comparable noise levels. That’s because of the use of a larger cross-sectional area, as well as the efficient impeller geometry that the Stratus 140 PWM definitely has. “Cheap” fan doesn’t necessarily mean “weak”, though of course there are some compromises based on more limited manufacturing resources than with more expensive fans.

You already know Endorfy Stratus fans from our tests of the 120 mm models. From these, we know that in addition to a great price/performance ratio, they are also characterized by a really high efficiency. That’s in the sense of high airflow per “unit of noise” compared to other fans. There aren’t many competing solutions, although yes, the Arctic P12 (PWM PST) are a tough competitor for the same price.

And then we know about Stratus 120 PWM fans that they have fairly high manufacturing tolerances and can exhibit different vibrations across individual pieces (from “none” to quite high), which is a certain tax for the fact that these fans can be really cheap. This is also true for the one number larger Stratus 140 PWM variants. These are also inexpensive and you can also expect a greater variance of vibrations, which can affect, for example, the “secondary noise” by resonating a case or a cooler’s heatsink. In short, what the fans are in contact with. But this applies to many fans and especially in this price range, where you cannot expect super-high precision in the manufacturing of individual parts. Particularly when it comes to the axle and rotor centering.

As such, the rotor of the Stratus 140 PWM has no visible defects that would result from its manufacture with injection molds. The sometimes critical edges of the blades are straight, free of indentations, and the surface of the impeller is essentially flawless in terms of workmanship.

The shape of the blades is characterised by distinctly curved leading edges with a rounder belly in the second half (of the blades, towards the tips). This is mainly for greater yield in the most aerodynamically efficient spectrum. Compared to the higher-end Fluctus (140 PWM) models, the Stratuses don’t have teeth on the leading edges of the blades, and mention of pychoacoustic optimizations seems to have disappeared from the manufacturer’s public product description. It is possible, therefore, that their basis was in this modification.

Upozornenie: With nylon dust filters that don’t have some sort of a reinforced mesh, this fan can get into a collision. The height difference between the frame and the impeller structure is too small and there is a risk of mutual contact resulting in excessive, extremely annoying noise.

However, the team around Synergy Cooling, who were behind the psychoacoustic optimizations (for Fluctus), are still to be involved in the development of these fans. And we believe that even with the cheaper Stratus fans, there was an effort to achieve the best acoustic performance possible. This depends on a number of elements, such as the shape, the material used or its thickness. As far as the flexibility of the Stratus 140 PWM blades is concerned, it is average.

The limiting factor with cheaper fans is the material budget, and when Endorfy couldn’t use a stronger polymer for these reasons, the “weak spots” are at least reinforced with more thickness – up to around 2.7 mm at the tips. The greater thickness also comes in handy here because the Stratus 140 PWM blades are really long. For the proportions of the format, they’re over the top. In fact, the area of the hub (with a diameter of 41.2 mm) is the same as that of the 120 mm models. This means that for the larger format (140 mm) the blades had to grow quite significantly, which increased their flexibility. And the more compensation there is with the greater thickness of material, the less risk there is of unpleasant vibrations that increase the noise level of the fan and possibly of what it is attached to.

   

The blades and also the impeller hub are comparable in size to the Fluctus 140 (PWM), so it won’t affect the results at this level too much in terms of airflow or static pressure. Stratus 140 PWM has a weaker motor (with 0,25 A), which is also related to lower maximum speeds. These are advertised “only” up to 1200 rpm (instead of 1800 rpm of the Fluctus 140 PWM). This is thus a slower rather than a more powerful fan.

The impeller geometry with relatively smaller blade spacing also predicts a versatile application for the Stratus 140 PWM, where performance characteristics include higher static pressure and therefore less airflow drop due to an obstacle than in fans with less dense impellers, which typically have two fewer blades. This Endorfy fan has up to nine of those.

The built-in cable is approximately 58 cm long, so it is quite long. But without the possibility of chaining the fans together. Unlike the Fluctus models (with two connectors), it only has a connector to connect to the motherboard or a splitter. In the package you will only find four self-tapping screws and a simple user manual.

Note: The Specifications chart, which used to be in the following place, is now on the second page of the article. We have reserved a separate chapter for it because of its growing size and the resulting relatively large height. This separation should thus contribute to better user control, especially on mobile devices with smaller displays.

And one more thing: To navigate through the result graphs as easily as possible, you can sort the bars according to different criteria (via the button on the bottom left). By (non)presence of lighting, profile thickness, brand, bearings, price or value (with the option to change the sorting to descending or ascending). In the default settings, there is a preset “format” criterion that separates 120mm fans from 140mm fans.


  •  
  •  
  •  
Continue:
Flattr this!

Related articles

Leave a Reply

Your email address will not be published. Required fields are marked *