My take on AC12025PWM (I have two such fans).

* Need to run it down below 800RPM before it approaches silence.

* Built in PWM splitter feature is quite useful if the only controllable header on your MB is the CPU.

* Fluid-Dynamic Bearing makes it well suited for use on a heatsink and should allow it to work equally reliably in any orientation.

i think ill take the plunge and buy one of the Akasa Apache 120mm and see how it is

i got the akasa apache and Arctic cooling one,

i can instantly tell that apache will be more silent.

holding both fans in my hands the plastic on the AC has a little give (flex) while the apache one does not even budge. build quality on apache is 5 stars, AC 4 stars

doing a simple test, i hold the fan in my hand and spin the fins. the AC one has a wobbling/vibration feeling in my hands. the akasa one has no vibration or wobble feeling. this is probably dude the build quality and secure packaging on akasa.

on the upside is the AC is $5 USD , the akasa is $15. if you have the money akasa is definitely better but if you are on a budget the Arctic is decent.

i havnt installed them yet so this isnt really including the sound of the motor, but considering how good my first impression with the apache is im thinking its a winner

anyone know where to get the apache in Australia? I'd love to try one.

That's great, thanks, please let us know when you have run them both and how they perform

Don't mean to rain on your parade, but there is absolutely no way of knowing what a fan would sound like without hooking it up. The only hints might be the shape of the blades and the rated speeds, which you didn't mention.

It very well may be the Akasa wins in terms of sound, but you don't know it yet.

BTW the hard plastic is not as common is silent fans as it is with led fans. Noctua, nexus, AC, scythe all use the soft stuff.

I just got my sample of Apache fan, albeit I haven't yet been able to plug it in here's few observation:

Soft mounbts are identically feeling and colored as Noctuas

Cord is covered with similar sleeve, have that exact sticky feeling and exact same scent of Noctua fans

Fan pacakge resembles greatly Noctua's

Scent of the fan and pacage is identical to Noctua's (all 7 Noctua fans I've had have had same scent), which is weird since usually fan's don't smell. Noctua's and Akasa Apaches have been first ones I've noticed this scent and this scent is same.

Assumption: Akasa Apache is made in same factory as Noctua fans or they share a lot same components and such. This is my initial conclusion. I haven't yet plugged the fan as I am at work and there aren't any PWM supporting machines.


Edit:
Open air test with Manual controller:

Full tilt @12v: Audiable motor noise, some tonality main noise is motor noise and air woosh. Generous amount air pushed in quite force.

@ 9v mark: Motor became inaudiable fast. Main noise is air woosh. A lot air was pushed Effectively Quiet.

@ 7v A slight bearing noise was audiable in few inch distance. Any further it would be overshadow rest components. Pushes still nice amount air. Quiet/Silent effectively. Around here seems to be sweet spot for CFM/RPM. Between 9v's and 7v's. (case and heatsinks can change this so this is just open air result which is meant to give guidance and not be absolute fact)

@ 5v: In audiable excluding minor bearing growling you can hear very, very close. Amount air was moved was still quite good, compearing that I've never really seen fan blades move that slow, except Slipstream 500 rpm. Exact rpm's unknown yet.


Next phase: in case test with rpm sensor attached and then how does PWM control work.

Initial summary: Too loud @12v but there really isn't many fans which are not. Becomes quiet very fast and is silent effectively in low rpm's. There is some slight bearing noise but its very faint. This fan seems to push quite a lot air with quite force compearing some other fans in similar speed.

Case test will truely tell how this fan will sound like. But if this keeps on in Case and heatsink, this fan is quite excellent choice for heatsink fan but we'll see. I'll post some opinions once I get them tested.

I tested mine the same way; it ran at 1400 rpm @12v rather than the 1300 rpm it is rated at. Same conclusions as you.

Well, fan headers do give different amount of voltages and such.

Heatsink test:
I placed that instead of my Scythe Kama PWM on HDT-S1283 heatsink.

Fan is rated 600-1300 rpm's. Mine is now rp'ming 480-500 rpm's, same as my Scythe Kama PWM. At full tilt Kama PWM is quieter and smoother. Apache pushes a lot more air with stronger force than Kama PWM. At 480-500 rpm on my heatsink, Apache is inaudiable over rest system.

Apache is also sturdier than Scythe Kama PWM. Kama PWM's blades with hub rattled with blades when fan was shaken from frame. Apache is a lot sturdier. No rattling.

In use, Apaches noise signature is worse from Kama PWM's in full tilt but quiets down fast while simple hand test I could feel Apache push more air thru heatsink than Kama PWM at same speed without increase overall system noise.

I am quite impressed.

Only negative marks I can find from the fan:

- Noisy when full tilt ( most good fans are noisy full tilt )
- Slight bearing noise (even it was just few inches away )
- Color?

Positives marks:

- High airflow and pressure when compeared fans at similar speed
- sleeved cord
- PWM
- Sturdy structure
- Color?

Apache is good addition to PWM fans, it may not be quietest as the best of the best but on low rpm's is definately good enough for a silent system. There are not too many PWM fans on market but Apache is one of the best ones I've so far tried.

With 50,000 MBTF and dust and moisture resistance design to get IP-54 military certification (this might just be marketing hype, I cannot verify this ) and the fact it pushes more air with higher pressure than compareable fans this is very good choice for a heat sink.

I think I'll transfer my Kama PWM into storage and keep Apache instead...

Thanks for the mini-review

As you have both of them, can you confirm that Apache has open corners and that the Scythe PWM does not. This is an important factor for some heatsinks such as the Noctua NH-C12P where the wire clips would be obstructed by solid corners.

Yeah, apache has open corners while Kama PWM has closed ones ( took me 15 mins to open up with saw, pliers, file and sand paper )

I got my Akasa Apache and NB multi-frame as well as Be Quiet SilentWings USC (non-PWM).

My NB was broken out of the box (one wire is loose) and I can't seem to be able to find my soldering iron. Sigh.

Akasa Apache is quiet enough and there's not much I can add to Jamppa's good mini-review and I can't compare it to the NB MF, so....

BeQuiet SilentWings USC are not very quiet, although they do push quite a lot of air (I have 120mm and 92mm models). There's also something about the ramp up noise, when you use them with a 3-pin fan controller (non-pwm) that makes them not well suited to SPCR setups. There's clearly more than just the wooshing sound there.

Now I gotta go find that soldering iron...

I am in the market for the best 120mm PWM fan. Fan will be mounted on my Prolima Megahalems so it needs to have the holes in the corners for the fan clips.

Right now after reading this thread and some others, I think it's down to one of these:

Arctic Cooling (model??)
NoiseBlocker Multiframe
Scythe Gentle Typhoon
Akasa Apache

I don't know how to make my decision - can anyone help?

You can eliminate Arctic Cooling. Their fans have never been top class in my experience, in SPL testing or subjective listening. NB Multiframes generally seem quite good but often develop a kind of buzzy "nnnnnnn" sound when spinning slowly. I personally haven't had any good experience with Akasa fans, but don't know that particular one.

That leaves only the Scythe Gentle Typhoon -- which many have described in these forums as the best ever, so probably worth trying. BUT these are definitely not PWM -- at least not the last time I looked, tho it's possible they released PWM versions since then.

I think the only 120 PWM fans Scythe offers are the Kama PWM.

Be Quiet SilentWings PWM fan line announce. I have no idea what they are like.

http://www.tcmagazine.com/comments.php? ... 63&catid=2

Nexus now has a 4-pin PWM 120mm fan. I have one but haven't tried it out yet.

The Scythe KAMA PWM 120mm has a sleeve bearing. From these forums I have learnt (if I have it right) that, as a general rule, you shouldn't use sleeve bearing fans in high heat situations or horizontally.

From Fan Roundup #5: Attack of the 120 Scythes part of Devon Cooke & Lawrence Lee's conclusion is:

Are they saying the Nexus 120 sleeve bearing fan has been used as a CPU fan?

Would the Scythe KAMA PWM be suitable as a CPU fan even though it is has a sleeve bearing?

The following is a quote from Tony Ou of Silverstone on the problems of sleeve fans in horizontal mounts:

The most silent and in the same time performing 12V 120mm fan is Scythe Silent Typhoon 1.450rpm.
I have 5 of them in my case and the most loud thing was the clicking of an hard drive (that was replaced with Intel SSD).

The fan is so silent you will hear only a very gentle airflow.

If you wish to shift only half of the airflow from this fan, there are others that are quieter as a whisper.

Five fans? Five 1450 rpm fans?

Hard drive louder?

What is going on in this place?

Yes, five Scythe gentle Typhoon 1.450rpm and (+) one 220cm.
For the air intake, that is.

The case is very big, you know.

Anyone get a chance to compare the Scythe Slipstream PWM vs Kama PWM?

Is there a US source for the Akasa APACHE Fan (AK-FN057)? Google is just coming up with UK sources for the fan. The US distributors on the Akasa web site don't seem carry this particular fan. As an alternative, a UK site which ships to the US without too much hassle would be useful as well. Thanks.

I was just looking at/researching PWM fans and I found it...

http://www.sidewindercomputers.com/ak12ap57cfmi.html

There you go, it's in stock this week too, a few days ago when I ordered it wasn't in stock so I opted for a couple Scythe Kama PWM fans from Performance PCs since hey sleeve for free and were a couple $$ less than frozencpu

Anyone know why the Scythe Gentle Typhoon 1450RPM and 1850RPM are out of stock everywhere?

well I received Scythe Kama 120mm and 92mm PWM fans (one of each) and installed them in my Acer server. The 120mm fan is nice and quiet, but without the aid of speedfan it doesn't spin fast enough and the server errors because the fan is spinning too slow. It also doesn't move enough air to adequately cool the unit. The 92mm fan is pretty loud at anything over 400RPM and buzzes something awful. Not sure what I'm going to do...


Anyone else have problems with the Scyythe Fans buzzing?

You don't get silence huh? No way in hell 1,450rpm fan is quiet. My 1,200 rpm slipstreams full tilt are to loud.

Noise is subjective since hearing is subjective. In my experience of GT's is that GT 1100 RPM's was less percievable than Slipstream at 900 RPM's... GT's are weird fans, even they spin fast they don't feel / seem / percieve as loud and their noise is very hard to actually hear and pinpoint. Now this is my experience based on 3 sample variance of GT's

You may be right, but 5 of them, at 1450 RPM, plus a 220mm fan... well that's what I call subjective silence!

I purchased a Gentle Typhoon 1450 to replace my SFlex on my Megahalems and there is a world of difference. Gentle Typhoon fans are amazing!