Everything changes with obstacles
It is made in the same injection mould as the FC120, but still has noticeably better properties. Stronger material, higher weight, different bearings and a more powerful motor make the FK120 one of the most attractive options among inexpensive fans. But that’s only assuming the “right” adjustment. Outside of that, this fan can be quite uncomfortable and ironically for the same reason it is sometimes unbeatable.
Everything changes with obstacles
So far, we have described how static pressure and airflow measurements are made under conditions where the fan has no obstacles in its path. In practice, however, fans do not usually blow into an empty space, but have a filter, grille or radiator in front of or behind them, the fins of which need to be pushed through as efficiently as possible.
We will also measure both airflow and pressure through practical obstacles for the reasons stated above. These include two types of filters that are usually used in PC cases. One fine – nylon and the other plastic with a thinner mesh. One other obstacle is the hexagonal grille perforated at 50%, on which the vast majority of fans – intake and exhaust – are installed. In some cases, we measure the effect of the obstacles on the results at positions (behind or in front of the rotor) that are used in practice. All obstacles are both pushed through to detect pressure drops, but also pulled through, which in turn speaks to the impact on airflow.
We use two radiators that differ in thickness and fin density. The EK CoolStream SE120/140 is 28 mm thick and the FPI is 22, the Alphacool NexXxoS XT45 v2 is thicker (45 mm) but with less FPI. CoolStream’s fin disposition is also similar in parameters to AIOs. The results on the NexXxoS will again be attractive for those who build their own water cooling loops, where the fans should work well even at low speeds – hence the lower fin density.
These obstacles and especially the radiators, but also the grilles, increase the mechanical resistance in front of the fan, resulting in higher noise levels. However, we will still tune the fan speeds to the specified noise levels of 31 to 45 dBA. Naturally, the speeds will always be lower than when testing without obstructions, but we will maintain the noise levels for clarity. The different noise levels with and without obstacles will only be at maximum power. In this mode it will also be nice to see how the fan design works with the obstacle and in which case the noise level increases more and in which less.
- Contents
- DeepCool FK120 in detail
- 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)
- Static pressure measurement…
- … and 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 by 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
Thank you so much for your hard work bringing us these reviews!
Greetings from Brazil!
Hello
Your expert explanation helped me make my final choice between the two DeepCool FK120 fans and the ASUS ROG Strix fan XF120.
The price difference of these two fans in Iran is insignificant and is around 5 dollars.
Overall, according to your tests, I would choose the Deep Cool fan.
I hope it is the right choice.
Your friend from Iran
Choosing the most suitable fan for a specific scenario is highly complex. In addition to the fact that all situations in practice are more or less different, each has a different set of priorities of individual characteristics. Someone may prefer lower vibrations to a slightly higher airflow, so that the fan does not end up being a source of excessive secondary noise in interaction with, for example, the case.
But when you have looked through our tests, taken a look at the context, evaluated the pros and cons, you must have made the right decision. 🙂
it would be more complex if we had more high quality fans on the market, but nowadays it’s mostly limited to whether you want maximum performance without noise or maximum performance disregarding the noise
in the first case you get A12x25 (or T30 if you have space for that), in the other probably some monster from Delta
if we had high quality fans optimized for specific usecases (like Noctua had in older generations, before releasing the overwhelmingly good A12x25) we could extend that choice to low vs high impedance, but nowadays S12A is entirely irrelevant and their static pressure fans are only used to save money