A concept in which an LCP impeller and ARGB LEDs meet is particularly rare. But it has enormous potential for achieving top-notch results. That is, as long as everything fits together optimally and there are no weak spots somewhere that increase the noise level. There are still a few things to tweak with the MagFlow ARGB fan, but already now, in its current form, it is a premium fan, and not only among lighted models.
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 impeller) 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.
Hmm, that’s worse than I thought for an LCP fan with Gentle Typhoon-like rotor, only trading blows with the much cheaper Arctic P12 ARGB. Perhaps the impeller footprint is the main culprit here, alongside the motor and bearing.
Comparison with the Grand Tornado would be interesting, as they represent two extremes of impeller footprint while having similar blade geometry.
Yes. Thank you for the heads-up, we have added one more negative to the +/- table, namely that the vibrations at some speeds are higher than they could be for the standards of LCP fans. There is probably some imperfection at the level of the bearings, for which this happens in combination with this impeller.
I have no doubt that the impeller itself will be well aligned and the fault will be elsewhere. At the same time, it won’t be some random thing, as these fans behave identically across different samples. It’s hard to say where exactly the weak point is, but maybe it could be suppressed or compensated for in some way. For example with balancing inserts, like the Phanteks T30. And maybe they wouldn’t help at all, there’s probably no point in speculating here and you just have to accept the fact that the vibrations can sometimes be higher for an LCP fan than one would expect.
Still, this is only Seasonic’s second fan and I have no doubt that with each new one more and more flaws will be removed and eventually the result will be very positive. We gave them a tip for an “Arctic P12 with an LCP impeller”. Personally, I would be very interested to see how such a design, with a very precise build, would stand up to, for example, the NF-A2x25 or the T30. I guess it might not be a bad thing, since even the P12, with its noisier low frequencies, which could be significantly suppressed after blade stiffening, ends up at the top of the performance charts. The question is whether with a significantly heavier impeller the small hub could be retained, as it could probably cause some instability.