Top price/performance in 15 mm – Arctic P12 Slim PWM PST

Arctic P12 Slim PWM PST in detail

Low-profile fans are often seen as compromise solutions that will not achieve the efficiency of thicker models. This may or may not be true. In practice, the Arctic P12 Slim beats a number of full-size fans. Sure, Arctic’s 15mm fan has many shortcomings, but these are vindicated by the very low price. In the 120mm format, it is one of the cheapest, but definitely not the “weakest” slim fans.

There is no need to be prejudiced against slim fans. If you find a fan with a half profile height fits your small case or on a cooler, feel free to put it there. Figuring out how to get a “standard” one in there after all, even at the expense of a smaller cooler heatsink, may turn out to be a worse option in the end.

We’ve already tested one 120mm fan with a reduced profile (to 15mm) – the Alphacool SL-15 PWM – this one from Arctic (the P12 Slim PWM PST) differs significantly in its design. The rotor has “only” seven blades, which is relatively small for this fan format, but it is not so surprising for Arctic. It uses fewer blades than usual even on larger fans. Anyway, the important thing is that even a smaller number of blades significantly fills the available cross-sectional area.

The spacing between the blades is relatively small, but this naturally means that a geometry of long, distinctly curved leading edges (blades) is chosen. This is a good thing on the one hand, as it is an efficient design without a conical trajectory of the air streams, but it comes at the cost of high flexibility. And although it cannot be said that the blades are completely thin and the thickness of the tips is “as much as” 2.2 mm, both for the length and the smaller width and height, the blades are quite flexible. Thus, some vibrations will be generated on them and these also translate into unpleasant resonant frequencies.

We can already conclude that operating at about 850 rpm is very inconvenient. The fan hums significantly (at 380 Hz), and the airflow is quite low in this setting, disproportionate to the high noise level. Upwards or downwards, however, the high noise level subsides, although resonant frequencies do occur quite often, at different speeds, but you won’t encounter a worse scenario than the one we pointed out above.

The rotor itself is taller than average for a 15mm profile fan. Support with nylon filters is nevertheless maintained. The height difference between the frame and the rotor is sufficient at the fan intake, even if you use a filter with an unreinforced mesh. But the worse ones, which collapse significantly, can already collide as with all fans.

But how come the rotor is above standard height then? There is very little spacing on the other side, between the rotor and the stator slats. It’s very tight there (which you’ll notice even with minimal deflection, typically when cleaning by wiping the blades), but in practice it doesn’t matter. In addition, all the stator slats except the one that runs the cable have an aerodynamic shape, their tips taper towards the blades.

The build quality is very decent for such an inexpensive fan, without significant imperfections, which are sometimes seen due to saving on injection moulds. However, don’t expect any extra extras or accessories – the frame is simple, with no anti-vibration pads in the corners.

The cable design is quite solid though. The insulation of the individual wires are glued one on top of the other, so the cable is thin, flexible, and nothing frays anywhere (as with some cheap fans with wires in a mesh). There are even two connectors on the end. One to connect its own motor, the other to connect a different one. The cable is 40 cm long (+ another 10 cm for the adapter for serial connection of the neighbouring fan).

* When reading performance values, a certain amount of tolerance must always be taken into account. For maximum speeds, ±10 % is usually quoted, minimum speeds can vary considerably more from piece to piece, sometimes manufacturers will overlap by as much as ±50 %. This must then also be adequately taken into account for air flow, static pressure and noise levels. If only one value is given in a table entry, this means that it always refers to the situation at maximum speed, which is achieved at 12 V or 100 % PWM intensity. The manufacturer does not disclose the lower limit of the performance specifications in its materials in that case. The price in the last column is always approximate.

• Contents
• Arctic P12 Slim PWM PST 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