I recently bought two of the aforementioned case fans and replaced some Scythes in my P182 for testing.

Quick rundown: surprisingly nice fans, especially at 8 euros a pop. The build quality is less than Scythe's (S-FLEX, Slip Stream). The PWM splitting function that is their trump card is okay but not great: it works but has limited reach. The fans wind down to very quiet levels at idle (30%, 20% is so inaudible it gets unnerving) and are unintrusive for me at load (70% typical). Full blast sounded rough, not acceptable.

Main observations:

1. CFM/dB seems good enough. Negligible performance and sound penalties for horizontal positioning.
2. Fans transition in RPM leaps under Asus mobo control (AI Suite, 30% @40'C CPU, 100% @60'C) but do not startle. No zig-zagging.
3. Unintrusive at idle (can hear rough characteristics up to 10 cm though), audible 'woosh' at load but remains unintrusive.
4. Flimsy frames, awfully thin wires.
5. PWM signal split happens at the connector, so all wires lead to the same damn place - gets crowded fast and limits reach considerably, you cannot wire an entire ATX case from the CPU_Fan connector.
6. RPM wire separated into its own connector and apparently needs its own connector (I took it from the instructions that I shouldn't put it through a chain, only a single connector's extension, see Observation 7).
7. Instructions poor but have big pictures, can roughly figure out what's supposed to happen.

Good for: people who want quiet and automated case ventilation on a budget, have (adjustable) PWM control and only need a couple fans.

Bad for: die-hard enthusiasts, anyone with fans in more than one place, mobos with no extra connectors post-install (for RPM).

Verdict: They're a keeper. You just can't beat automation.

PS. I'm working on circumventing the RPM hassle (if I'm reading this right, you're NOT supposed to plug RPM into a chain) with an Akasa PWM splitter cable.

I'll let you know how that goes.
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Edit1: Welp, the Akasa cable works much better than the Arctic solution, gives me easy and straightforward access to RPM and gives more amperes to work with to boot! Only downside is poor connector and plastic quality, but that's an Akasa tradition

If you're buying PWM fans, this Akasa cable is a good choice!

Thanks for the review. I have three of the older models in my work PC using the PWM sharing feature to run all of them. 120mm on the front and back of the case and 92mm on the CPU. No problems routing the cables for to all of them. Although the Akassa PWM splitter cable looks really nice. And it's better for the MB since it gets it's power from the PSU. Rosewill has the same thing on Newegg.

Is there any clicking with your fans at low speeds? That's my only real beef with my AC fans. They're not quiet enough for my home PC which is VERY quiet. The clicking is noticeable when they're not spinning fast enough to drown it out with whoosing and is probably more annoying than the whoosing.

Cheers!

The additional power I can get with the Akasa cable was the main reason I bought it. It would be doable to wire both exhaust fans and the CPU fan with the Arctic system, but I would run way short on the front and PSU fan in the P182. Also, this Akasa cable could use some SERIOUS sleeving, it's a mess if you wire it without any sort of management.

I did have your experiences in mind (from the Donation topic I think) when I set out to test these fans, and sure enough, there were and are some ugly warbles at low RPM. Those don't carry far though, and at a distance of about 1+ metres these sound okay for my quiet-not-silent rig.

These are not the best choice (but one you can consider) for hardcore enthusiasts, but I'm glad I tried them - they suit my gaming/work rig just fine, as the automation makes up for slight shortcomings.

Addendum: I was playing Minecraft for a short while and in the early stages of the game I heard an odd noise. After listening attentively, it started sounding like someone's tyres squealing off in the distance. When it went on for a good while, I got nervous and listened to the new fans and BAM: at a certain RPM, the horizontally mounted one makes a horrible, grinding type of sound. It is not loud (hence the "in the distance", but it is unnerving), and it did go away at higher RPM, but this just goes to show the difference between a fan that costs 8 euros and one that costs more than 15: CONSISTENT performance.

In short - AC fans okay at low RPM and high RPM, trouble may lurk in between the two!

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As I am currently unable to pinpoint the PWM % and RPM this occurs at, take this observation with a pinch of salt. It might be some other fan I just haven't spotted yet. My fingers are crossed it's not the 460 GLH as it has been pleasant so far...

I can get them for 4 € plus shipping, or 5 € for the Pro variant: that's unbeatable value, though there are much better choices if one can spend some extra cash. Problem is, to get better quality and durability one has to spend at least 3 times as much, that's why I keep recommending them to basically anyone.
The 92mm variants IMO are better than anything one can buy today in that size, while the 80mm one is just too speedy to be of any use, silence-wise, unless heavily undervolted.

Ps: The 3 pin variant is an excellent PSU fan, with its low starting voltage and high pressure. Apparently, the 80mm one is highly regarded in this field.

You're right about the value; whatever the country and customer specific price may be, it is roughly half or even a third of the price of a Scythe fan. If you're on a budget, this is a breed of fans to consider.

For me it was the PWM and innovative control aspects that sold the fans, so you not only get decent performance but innovation as well. Hard to beat that.

PS. The noise I heard earlier is not the AC PWM fans, at least no amount of testing now can reproduce it. It's not the GPU HSF either... so that just leaves power squeal. Which is nigh-impossible to cure. Luckily the noise hasn't been recreated after I swapped my RAM, so fingers crossed...

Regarding the noise: it's power squeal. Played a game at 1000 FPS today and the video card sounded like it was going to explode. VSync to the rescue!

The AC fans: a-okay for sound at all RPM.

Thank you for the review, really appreciate it since i'm considering buying those.

mind if I ask: at mid-low rpm's how do they compare to the scythe's you previously had?

Cheers!

It's hard to compare objectively when I haven't listened to both side-by-side, but the main difference is perhaps that the sound is not as silky-smooth. These shouldn't be any louder at least, since my previous fans were S-FLEXs and not Slip Streams, which probably produce less mechanical noise (motor). I would not hesitate to recommend the Arctic Cooling fans instead of S-FLEX fans for your typical, unimpeded case fan scenario.

Cheers!
These fans indeed impressed me greatly as they performed wonderfully in my open test rig. I'll second your opinion.

Honey, you had me at the word "budget." I'll take your word for it. If it's really as good as you're saying it is, I may very well invest in one of those fans. I will take a look at some of the other reviews and if they seem to be the equivalent of yours, then I guess Arctic has +1 customer.

Thanks for sharing your review with us, Das!

Hi, I like the AC F series fans too, in fact of the 6 variations I've got 4 in my PC, 7 fans total!
3x 80mm, 2x 92mm PWM, 1x 80mm PWM and 1x 120mm PWM.
At idle it's pretty darn quiet, 120mm ~ 550rpm, 92mm ~ 600rpm and 80mm ~ 650rpm. I think the 92mm fans are the best, very smooth/quiet but the others not bad either and so cheap for fluid bearing / 6 year waranty items. (QuietPC.com has them £3 ~ £5)

Regards, Seb

Recently I bought a pair of AC F12 PWM as well.
comparing to my previous Slipstream Slim, there is much more airflow at lower noise levels.
Hooking them up to the pwm fan of my scythe katana makes them perfect

now the biggist noise source is my vx450

I've had one of these fans on my CPU for a little over a year. Using Speedfan, I slow it down to ~600 RPM and it is very quiet.

But...lately I've noticed that when rebooting (when the fan runs at full speed), it is getting noisy, kind of a buzz/click sound. This of course goes away once Speedfan starts up. Thought others might want to know...

That's good info, thanks. How hot does your CPU get, seeing as it's overclocked? I'm thinking that might be hurting the fan, as it's meant to serve as a case and not a HS unit. Shouldn't be a backpressure issue with the Ninja.

I'm still some months off the 1 year mark, but the fans I use haven't changed in character in all this time. One is mounted vertically and one horizontally, so it seems the bearings can at least handle that (so far).

Edit1: The AC site lists the bearing type as "FDB", so HS use shouldn't hurt - but in this price category you can never be quite sure of the implementation.

The CPU runs at 60C 24/7 folding. The fan sits between the DRAM and the Ninja (you may recall this from my SuperQuiet SuperClocked article), so the air flowing over the bearings is probably about 40C; the DRAM heat sinks are warm to the touch. The fan is mounted vertically, blowing through a duct across the Ninja out the back of the case.

60 'C sounds awfully hot, especially if it's around the clock. Obviously that's just the CPU and the bottom of the heatsink hovering at that mark, but I'm thinking some of that heat will get conducted and radiated to the fan, with nowhere to go but the hot-ish (in your case, no pun intended) case air. I've never had an IR thermometer so I haven't been able to take measurements, but have you measured the temperature of your fan's hub?

For reference, my fans have been running in a case with the ambient well below the 30 'C mark some 80% of the time (work or browsing), and certainly not 24/7 (about 10 hours daily). The latter means yours have done way more operating hours at least. RPM the same.

In any case I doubt that the case's ambient temperature is the main criteria manufacturers use when they recommend one fan over the other for heatsink use, though it's certainly going to be a factor. From what I understand it's the different pressure scenario (mfgs) and concerns over the total heat load for the fan (SPCR reading), as well as the reliability of the bearings (sealed, double etc.) in the first place.

That, or this could all just be sample variance and all my speculation a moot point.