There have been some interesting reviews on the 80mm fans, and some on the higher speed "E" 120mm fans, and other websites have shown some good figures on these D fans so I thought I'd buy a few and try them. I purchased 4 from pccasegear.com in Australia. They were excellent in delivering them less than 24 hours from my order to my door.Scythe S-FLEX 120mm Fan SFF21D
Features for Scythe S-FLEXâ„¢ 12cm Case Fan
Equipped with Genuine S-FDB* Bearing
This fan is equipped with genuine S-FDB (SONY Fluid Dynamic Bearing) made by SONY corporation.
Market Leading Low-Noise Level
S-FDB technology drastically eliminates the friction between the bearing and the shaft which makes this fan nearly inaudible to human ears. Additional suction magnet optimizes the magnetic force balance within the rotor to achieve the absolute silence. To further achieve the absolute silence, the fan is equipped with the Linear drive IC for reducing electromagnetic noise.
Outstanding Long Life of 150000 Hours
Patent Pending "S-FDB" structure allows the fan to last up to 150000 hours.
Anti-Shock Ability
Conventional ball bearing carries a point contacting structure for the rotation, which gives point supporting situations at dropping impact to damage ball bearing surface which could cause irregular noises. The S-FDB carries a surface contact mechanism for improved anti-shock structure, which is 5 times stronger than the conventional ball bearing.
Scythe S-FLEX 120mm Fan SFF21D
Features for Scythe S-FLEXâ„¢ 12cm Case Fan
Equipped with Genuine S-FDB* Bearing
This fan is equipped with genuine S-FDB (SONY Fluid Dynamic Bearing) made by SONY corporation.
Market Leading Low-Noise Level
S-FDB technology drastically eliminates the friction between the bearing and the shaft which makes this fan nearly inaudible to human ears. Additional suction magnet optimizes the magnetic force balance within the rotor to achieve the absolute silence. To further achieve the absolute silence, the fan is equipped with the Linear drive IC for reducing electromagnetic noise.
Outstanding Long Life of 150000 Hours
Patent Pending "S-FDB" structure allows the fan to last up to 150000 hours.
Anti-Shock Ability
Conventional ball bearing carries a point contacting structure for the rotation, which gives point supporting situations at dropping impact to damage ball bearing surface which could cause irregular noises. The S-FDB carries a surface contact mechanism for improved anti-shock structure, which is 5 times stronger than the conventional ball bearing.
Specifications for Scythe S-FLEXâ„¢ 12cm Case Fan
Model Number: S-FLEX SFF21D (800rpm)
Dimensions: 120 x 120 x 25mm
Specifications: 800rpm Version: 33.5CFM / 8.7dBA / DC12V / 0.10A
Connector: 3-pin (4-pin adaptor included)
Cable Length: 30cm
Bearing Type: S-FDB (Fluid Dynamic Bearing by SONY Corporation)
MTBF: 150 000 hours
S-FLEXâ„¢ is a registered trademark of SONY Corporation
They come packaged in a stiff plastic shell with an outer plastic wrapper.
(most photos have enlargements just click on them)
The detail on the top of the package says the fan appears to be basically made by Sony.
Lots of advertising bullsh... jargon on the back.
The contents are pretty standard 3 pin based, with a 4 pin adapter that nicely includes an rpm monitor you can plug in
The fan has all important partially open corners and looks like so close up:
Finally they mount without a hitch on the Thermalright ultra 120 (one of the uses I had in mind for them)
Ok so on to the review.
On visual inspection there are no outstanding features of this 7 blade fan and it has zero bling value which to me is a good thing. It is about average weight for a fan of this size (unlike say the Aerocool fans which are much lighter).
I'm fortunate in that I live in an extremely quiet area and the downstairs of my house at night is nigh on silent where a Nexus 120mm fan at 12V is downright noisy.
So I plugged it in and fired it up via various means. Many of my colleagues have criticised me at work for giving the bad news last which always downplays things so I'll reverse my usual stance, and do the ugly, the bad and then the good.
Bear in mind that this fan runs at 800rpm at maximum voltage...
This fan buzzes like a blowfly in heat with pwm control so that as an option to undervolt it is basically out.
8.7dB? Not in your wildest dreams. I certainly didn't believe it on the ad alone, and in the flesh I could tell it definitely was not 8.7dB.
Most fans are known to start at 7V. This one? Nope.
So it doesn't really start at low voltage. However it did go down in voltage once started, but I was not really happy that the way it ran at 7V would be reliable. A zalman fan mate was a decent match for it, but could easily drop it to a speed below which it refused to turn.
Ok that's the ugly and the bad out of the way. Now onto the good.
Vibration in the hand test? Very little, and almost nothing transmitted to the heat sink when it was mounted even without the rubber stoppers included in the ultra 120. Actually at equivalent voltage/speed the Nexus felt slightly smoother, but it didn't seem to make an audible difference.
This is one damn quiet fan at full voltage. At 12V I compared its noise signature and apparent loudness to a Nexus 120mm at 7V. They are very similar in loudness, with a higher pitched sound from the s-flex. Neither fans' sound characteristic was unpleasant. Furthermore it didn't make a difference what direction I held the fan at which may be nice for unusual position mountings of PSUs and heatsinks. The s-flex was only really audible in the presence of other components when I got up close to it (less than a foot). Mounted on the heatsink it almost seemed quieter (but that could have been my imagination), however it definitely was not noisier. Once mounted in the box I could not discern the sound of the fan over any other components, the WD5000KS suspended in an Antec Solo being the loudest.
Well the main attraction for me to this fan was that it was going to be probably the right compromise in terms of flow and noise at default voltage. I still feel uncomfortable running too many 7V things off the 12/5V split from the power supply since potentially I could feed back voltage to the PSU since less and less components are using 5V. The zalman fanmate was great apart from the fact it didn't let you turn it up to maximum voltage since there was always a drop. And pwm has failed to impress me on most fans I've used it on so it's something I basically never use except for one unusual fan I got in the past that seems to love it.
So what is my conclusion? Compared to the reference? The Nexus 120mm is a more versatile fan overall since its flow has greater flexibility at different voltages and can reach higher levels but at equivalent revolutions there is barely anything to distinguish them. There is great appeal in a fan that is working at the manufacturer's settings and achieves noise levels I desire. There is also the theoretical longevity advantage of the bearings, and the open corners that don't require cutting. Conclusion is that if you do not want to fiddle with voltage and want something below the noise level of other components, then this is the fan for you. Otherwise get a Nexus. In Australia, at least, these fans are priced almost the same.