Arctic P14 Max in detail
The culmination of our trilogy of tests of Arctic’s 140mm fans is here. With the P14 Max, the designers have worked on improvements that change both the acoustic properties and performance of the fan. The main new feature, the hoop, allows for, among other things, a significant speed increase, due to which this fan can have a really high airflow. On the other hand, fans of extra low speeds will not be too pleased.
The Arctic P14 (PWM PST) and Arctic P14 CO (PWM PST) fan tests are already behind us and now we’ll add the last piece to the puzzle – the Arctic P14 Max. This model came out only recently. With features that put this fan in a better light at first glance. This is matched by the highest price yet when it comes to fans from the Arctic P series.
The geometry of the P14 fans is extremely efficient, as you already know from previous tests. The noise level in the purely aerodynamic band (300-400 Hz) is relatively lower also because of the smaller number of blades, of which there are only five. This means that there is also less unwanted turbulence at the intake, at the leading edges of the blades. This reduces the noise level and also increases the pressure/airflow at the same time. Fewer blades does not always mean a “better” result. The latter is also dependent on the exact shape (of the blades) or additional surface details. The P14 Max does not have these, but the impeller consists of “only” five, distinctly curved blades. And particularly really long ones.
The difference in blade length compared to the simpler P14 (CO) models is virtually non-existent here, which is not the case with the 120mm models (the hoop variants, including the P12 A-RGB, have shorter blades), as they have a significantly larger impeller hub. The one in the P14 Max occupies the same total cross-sectional area as in the base P14 model.
Despite this though, the P14 Max blades are a little shorter, but really only by a hair, which the hoop steals for itself. Its role is twofold. Firstly, it stiffens the otherwise flexible blades, and secondly, it increases the pressure at the ends of the blades. In fact, the air streams don’t break away from them as much as they do with fans without hooped impellers, which results in a slight decrease in airflow. That is, as long as everything is the same and the only difference is the presence of the hoop. And you can verify that this is indeed the case by comparing the airflow of the P14 Max with the P14 at the same (or very similar) speed. At similar noise levels, the P14 Max may already be lagging behind, as there is another variable coming into play here that may not be affected positively by the hoop. But it also may, it’s a case by case situation.
As with the P14 and P14 CO, a material (PBT) with relatively lower stiffness is used for the blades, offset by greater thickness at critical points. And by the hoop. Without it, due to excessive vibration, this impeller design could not be reasonably operated at the very high speeds that are one of the main strengths of the P14 Max. Here Arctic ramped up from 1700 rpm (P14 and P14 CO) to 2800 rpm. And if the hoop wasn’t used, the vibration could easily get out of control already. They would be too high.
At such high speeds, which the P14 Max achieves for a 140 mm fan, vibrations cannot be completely avoided. Although we praised the cheaper P14 (CO) models for the negligible vibration on the frame, these were still significantly slower fans that didn’t necessarily need rubber pads in the corners. With the P14 Max variant, however, the anti-vibration elements already make sense, as especially at high speeds they will be useful in terms of vibration damping. These are, of course, also there with the P14 (CO) with some worse pieces, but in this case (P14 Max), higher vibrations are to be expected whenever you want to operate the fan with the highest possible airflow in mind. In this respect, records are being broken. Even the BeQuiet! Silent Wings Pro 4 (BL099), which is one of the faster 140-millimeter fans, is slower compared to the P14 Max.
The anti-vibration pads also improve compatibility with dust filters somewhat. By being slightly protruded from the fan body, they move the dust filter frame away from the impeller, and even with unreinforced nylon filters, there is no longer the potential for mutual abrasion as there is with the cheaper P14 (CO) models without anti-vibration pads. At its widest point (~28.4 mm), however, the Arctic P14 Max’s profile already attacks thirty millimeters. And greater thickness means potentially worse compatibility. Especially on radiators in ceiling positions, where the radiator (with P14 Max fans) will more often collide with coolers (or memory) on the motherboard.
There is 0.35 A listed on the motor. However, this figure refers to the electric current at maximum operating power consumption rather than to the motor power (allowing some tolerance for “inferior” pieces). The latter is considerably higher (than 4.2 W).
The fan is powered via an approximately 42 cm long cable with a 4-pin connector. There is PWM control support, but the option of daisy chaining (PST) with multiple fans connected to each other is missing from the P14 Max.
In addition to single unit sales (with the code ACFAN00287A), the Arctic P14 Max is also available in large packs (ACFAN00290A) that contain up to 5 fans.
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.
- Contents
- Arctic P14 Max in detail
- Overview of manufacturer specifications
- Basis of the methodology, the wind tunnel
- Mounting and vibration measurement
- Initial warm-up and speed recording
- Base 6 equal noise levels…
- ... and sound color (frequency characteristic)
- Measurement of static pressure…
- … and of airflow
- Everything changes with obstacles
- How we measure power draw and motor power
- Measuring the intensity (and power draw) of lighting
- Results: Speed
- Results: Airlow w/o obstacles
- Results: Airflow through a nylon filter
- Results: Airflow through a plastic filter
- Results: Airflow through a hexagonal grille
- Results: Airflow through a thinner radiator
- Results: Airflow through a thicker radiator
- Results: Static pressure w/o obstacles
- Results: Static pressure through a nylon filter
- Results: Static pressure through a plastic filter
- Results: Static pressure through a hexagonal grille
- Results: Static pressure through a thinner radiator
- Results: Static pressure through a thicker radiator
- Results: Static pressure, efficiency depending on orientation
- Reality vs. specifications
- Results: Frequency response of sound w/o obstacles
- Results: Frequency response of sound with a dust filter
- Results: Frequency response of sound with a hexagonal grille
- Results: Frequency response of sound with a radiator
- Results: Vibration, in total (3D vector length)
- Results: Vibration, X-axis
- Results: Vibration, Y-axis
- Results: Vibration, Z-axis
- Results: Power draw (and motor power)
- Results: Cooling performance per watt, airflow
- Results: Cooling performance per watt, static pressure
- Airflow per euro
- Static pressure per euro
- Results: Lighting – LED luminance and power draw
- Results: LED to motor power draw ratio
- Evaluation
Really, really interesting results.
I have heard that the P14 max suffers from motor noises, but it’s clear now that it’s only at <900 RPM where it's unstable.
The outer ring having almost no impact on noise profile is very surprising. Well, at least in the no obstacles environment. The huge impact of the ring on noise profile on radiators, despite having no effect otherwise, is even more surprising. Perhaps the back pressure cause deformation of the blades or something like that?
P.S. The links to radiator frequency plots are broken in the English version.
Thanks, fixed! 🙂
From the measurements on the fan frame, we know that the P14 Max is not a source of significant vibrations even at medium speeds, and yet the tonal peaks at low sound frequencies are quite high. We can assume that the vibrations on the blades will also be very weak and in a situation on a radiator, due to its resistance, the character of the vibrations may change. And they may move out of the unpleasant resonant frequencies. I guess it could be like this, that is, unless someone comes up with a more realistic theory. 🙂
Anyway, the fact is that the color of the sound on radiators is quite pleasant. That is, on our testing ones. Of course, you can’t generalise this.
The unpleasant tones that occur at certain RPMs are primarily from blade and frame spar resonance, and the source of their excitation is essentially unrelated to aerodynamic factors, and is primarily from the torque ripple of the motor. You can test the frequency of the anomalous tone at a particular RPM, and the RPM at which it occurs and the frequency of the sound wave will form some sort of mathematical relationship to the number of poles/coils in the motor (i.e., the frequency of the motor’s torque ripple) and the RPM at which the anomalous tone occurs won’t change, regardless of whether you increase the impedance or create a pressure pulsation that interferes with the blade’s aero-dynamics work.
Distinguishing a resonant noise from a blade or frame can be accomplished by observing a significant increase in frame vibration at the onset of the anomalous tone, and by observing a diminution of the anomalous tone when the frame tabs are pressed down.
However, note that in high speed (e.g., 4000+ rpm for 120mm fans) plastic impeller fans, the frequency of blade resonance rises slightly at high rpm due to pre-stress from blade deformation. The intrinsic frequency depends mainly on mass distribution and rigidity, and it is not easy to balance mechanical reliability and aerodynamic performance.
https://noctua.at/en/custom-designed-pwm-ic-with-scd
It would seem like this technology is a (partial) solution to this problem. Are there other ways of mitigation?
That wind tunnel looks great!
Did you have a chance to check whether the p12 max has the same instability issues at low rpm?
I have heard from users that it’s also a problem for P12 Max. ThermalLeft’s tests collaborates with this, where the P12 Max has relatively strangely low airflow at the lowest and second lowest noise settings (corresponds to roughly <=1150 RPM).
That’s exactly what I was looking for. Thanks a lot.
Not yet. But I believe that sooner or later we will get to it. But it will be as M writes, referring to the ThermalLeft’s results database. Fans with an extremely wide speed range usually have higher minimum speeds, unfortunately. Especially when it comes to cheaper models, which include the Arctic P12 Max.