Massive Fan Shootout: 25 Products
from Arctic Cooling, Cooler Master, GlacialTech,
Scythe, Titan, and Zalman

Arctic Cooling, Cooler Master, and GlacialTech

Contents:

1. Review: Arctic Cooling, Cooler Master and GlacialTech
2. Review: Scythe, Titan and Zalman
3. Test Results: 80x80x25 mm fans
4. Test Results: 120x120x25 mm fans
5. Annex 1. Noise profiles (1/3 octave analysis), 80x80x25 mm fans
6. Annex 2. Noise profiles (1/3 octave analysis), 120x120x25 mm fans

Paying close attention to various cooling systems for CPUs, GPUs, hard drives, etc., we often take no notice of some very important parts of these - fans. In practice, today fans are not just some cooling parts. They have obtained the status of independent products — that's how fans of the most popular sizes (80x80x25 mm, 92x92x25 mm, and 120x120x25 mm) are perceived now. A similar metamorphosis happened to CPU coolers that are gaining higher position in the hierarchy of cooling systems. For example, they were just like an alternate set of sundries in the end of 90s of the last century. Even major computer stores could offer only a couple of simple coolers to replace the standard models installed on Intel Pentium 100 or AMD K5 133. As for now, coolers are an active and significant segment of the computer market. Its growth rates are much better than in many traditional IT fields. It is not inconceivable that fans will play just as important role, considering the current market trend to promote PCs as consumer electronics (in other words, computers are becoming entertainment centers to replace many consumer AV devices) as well as support for a new class of products - DIY coolers, which offer enthusiasts lots of options.

The situation in the fan camp is evolving and we cannot ignore it. Today we are going to examine a group of 25 products (80x80x25 mm and 120x120x25 mm) from Arctic Cooling, Cooler Master, GlacialTech, Scythe, Titan, and Zalman. We'll analyze their technical and functional properties. OK, let's start the ball rolling!

Arctic Cooling Arctic Fan 8, Arctic Fan 8L, Arctic Fan 12, and Arctic Fan 12L

The shootout starts with models from Arctic Cooling — "inverted" Arctic Fan 8 (80x80x38 mm, 2000 rpm) and Arctic Fan 12 (120x120x38 mm, 1500 rpm).

A distinctive (practically unique) feature of Arctic Fan 8 and Arctic Fan 12 is their crafty case design — there is no case as such, a stator with an impeller are mounted on a frame with a special rubber suspension system to dampen vibrations. We should also mention the inverted stator-impeller block. Owing to this design, the impeller rotates clockwise (the other standard fans rotate counterclockwise), which may be a considerable advantage for unusual usage of Arctic Fan 12 (it will be described later).

These models are also well designed in terms of aerodynamics — the seven-blade impeller of Arctic Fan 8 and Arctic Fan 12 features a weighted selection of parameters intended to minimize noise and provide sufficient performance potential.

Arctic Fan 8: sweep and lean blade, variable blade chord (the distance between the front and rear edges of the blade) — 20 mm at the inner diameter (at the hub) and 28 mm at the outer diameter of the blade, tight arrangement of blades — solidity factor (chord-pitch ratio) is 1.25 at the hub and 0.87 at the outer diameter, normalized attack angles — 50° at the hub and 35° at the outer diameter, hub-tip ratio - 0.47.

Arctic Fan 12: sweep and lean blade, variable blade chord — 24 mm long at the hub and 33 mm at the tip, chord-pitch ratio - 1.2 at the hub and 0.66 at the tip, sparing angles of attack — 40° at the hub and 25° at the outer diameter, hub-tip ratio - 0.43.

While Arctic Fan 8 and Arctic Fan 12 look very well in aerodynamic terms, the technical image of these fans fades a little in mechanical terms — although they are equipped with improved sleeve bearing (this one consists of two sleeves — inner surface of the first sleeve is polished and mated with the shaft, the second has a larger inner diameter and rough surface covered with soft lubricant that holds oil), this is hardly "fluid dynamic bearing " (according to Arctic Cooling specs).

We also have some gripes with the electric binding of the engine — the inductor is controlled by a simple Anpec APX9140 chip, which only advantage is its ability to work with low voltages — starting from 3 V. There are no additional smoothing capacitors, which are usually used in such circuits to clip reverse voltage surges and protract the front-decay of switching impulses in the inductor coil. It leads to a noticeable component in fan noise - co-called engine popping (noises in the stator-impeller block caused by switching inductor coils).

And perhaps the biggest gripe — performance of Arctic Fan 8 and Arctic Fan 12. Despite the advanced impeller, these fans demonstrate weak performance in our testbed. They are outperformed by practically all contenders. The situation with noise characteristics is ambiguous as well (especially what concerns Arctic Fan 12). To all appearances, it's the fault of the open frameless design of Arctic Fan 8 and Arctic Fan 12 — the impeller actually works in the propeller mode here - with intensive vortex formation and significant pressure loss. As a result, fan performance slumps in a section with high impedance (our reference test heatsink), they generate minimum airflow. When in slow mode (1500 rpm for Arctic Fan 8 and 700 rpm for Arctic Fan 12), there is practically no effect from them.

What concerns the other two Arctic Fans — Arctic Fan 8L and Arctic Fan 12L, they are complete aerodynamical copies of Arctic Fan 8 and Arctic Fan 12 and differ in lower speed (1500 rpm in Arctic Fan 8L and 1000 rpm in Arctic Fan 12L).

There are no differences in technical and functional terms either, except for control electronics — Arctic Fan 8L and Arctic Fan 12L use the popular ATS277 chip, they are equipped with smoothing capacitors and demonstrate improved noise characteristics, owing to silenced popping of the engine.

Contents:

1. Review: Arctic Cooling, Cooler Master and GlacialTech
2. Review: Scythe, Titan and Zalman
3. Test Results: 80x80x25 mm fans
4. Test Results: 120x120x25 mm fans
5. Annex 1. Noise profiles (1/3 octave analysis), 80x80x25 mm fans
6. Annex 2. Noise profiles (1/3 octave analysis), 120x120x25 mm fans