I have been using a Nexus Real Silent D12SL-12BW 120mm fan (sleeve bearing design), mounted horizontally, on a Prolimatech MegaShadow CPU heatsink for about two years. Recently it started making noise, so it may not last much longer. It's a 1,000 rpm fan, with 3-pin connector, connected to a Nanoxia PWMX 3-Pin to 4-Pin PWM Converter/Adjustable Fan Speed Controller.

While researching replacement fans, it looks like Nexus makes a Pulse-Width-Modulation fan (Nexus D12SL-12 PWM Clear 120mm Case Fan 76CFM 15dBA, 500-2000rpm), but probably still uses the sleeve bearing, which is not recommended for horizontal mounting. Scythe S-Flex and Kama Flow 120mm fans get excellent reviews for quietness and can be mounted horizontally without problems, but I don't see any with PWM.

Is there a good (by SPCR standards) 120mm fan that can mount horizontally AND has a 4-pin PWM connection?

Thank you,

Scott

There have been good reports for the Noctua NF-F12 PWM 120mm Focused Flow fan. Noctua have gone to some lengths to make this fan as quiet under PWM mode as possible. It has a 300 to 1500 rpm range. PWM is simply thermal control, the fan will run relatively slowly at idle and only speed up in response to load and/or increases in ambient temperature. The value of it to some extent depends on what control your motherboard BIOS allows. It may be enough to rely on the automatic setting. Alternatively the motherboard BIOS has a SmartFan function that allows temperature related settings to be specified, and there should also be a manual option.

Nope, avoid the NF-F12 PWM, it is almost unable to be silent... if you like to stay with Noctua, prefer the NF-P12 PWM at least...

You can also check Noiseblocker PL-PS or M12-PS, new revisions are ok in horizontal position and thay are really good fans. Maybe prefer the PL-PS for radiator use ?

The NF-F12 PWM is more efficient than the the NF-P12 PWM as a cpu cooler fan. The F12 will cool slightly better at the same rpm, or you can run the same temperature with slightly slower rpm. At its full 1500 rpm speed the NF-F12 is noisy, but the motherboard BIOS controls can be used to limit top speed. Given the cooler here, the motherboard BIOS could be set to an intial setting of a minimum of around 30% and a maximum of around 80%. This will retain the PWM automation while balancing the processor temperatures against CPU cooler fan noise. If possible, the NF-F12 should be limited to a top speed on around 900-1000 rpm but the BIOS settings can be adjusted depending on what levels of CPU temperatures and CPU fan noise the individual user finds acceptable.

Sure the NF-F12 is more efficient...but the NF-P12 is not ridiculous, and the NF-F12 is way louder at the same rpm. Though even on a MegaShadow, I still think the NF-P12 PWM, or the Noiseblocker PL-PS are better choices

That is disappointing to hear. What is the source of your info?

If you were fine to live with out PWM i would go with a Scythe Gentle Typhoon, they make them in a wide range of values, i own 5x 1850rpm AP15 (if i remember correctly), i can undervolt them about 500rpm fine, and its design with a real ball bearing should be better for a horizontal placement, but its not as quiet as Scythe Slipstream or Nexus Basic. In the past, a lot of years back, Scythe SFlex were recommeded over Slipstreams for horizontal placement due to the design of bearing.... I had 3 sflex 1600rpm on a notebook cooler for couple of years (horizontal) and they were fine, why do i mention this..... because the Scythe Kama Flex 120mm PWM Fan (SA1225FDB12H-P) is almost identical to my old sflex, just its pwm (300-1600rpm), i have 5 running in my HTPCMI (check sig). one is horizontal on the GPU, and its doing fine, and they are running at 250-300rpm, but you can set to whatever you want, as long as you mobo allow it, bad news is availability, its almost out of stock in the usual places... but amazon with 3rd party sellers have some and here is another here seems to have them in stock. Heres a couple of pics for you to see,



Btw i also own 2x PLPS (check sig micromi build), and they are wonderful fans, but i havent tested horizontal, but this would also be a good pick, as long as you dont want super low speeds, like the kama flex can.

Well...get one, and you'll see by yourself
By silent, I mean not discernable without a hard drive spinning...if you have a hard drive (or many), for sure the NF-F12 PWM could appear silent for you, because running @300-400rpm it can not be considered noisy, but it is still noisier than NF-P12 PWM (mostly a small ticking, that I find annoying). Also remember I have only tested two samples of NF-F12 PWM.

Among other PWM fans, the NF-F12 PWM and NF-P12 PWM will be reviewed on a PWM fan roundup on Hardware.fr...soon to be published I think.

As for Kama Flex PWM, they are discontinued :/

Edit : Noiseblocker PL-PS run at ~450rpm @5V and ~280rpm @4V. Mine start around 4,2V.

I think these are both goods sets of advice.

I don't believe SPCR has ever found a PWM it really liked in terms of sound performance. That includes the Nexus PWM. I would expect that if any PWM fan would meet with SPCR's approval, it would the new Noctua PWM fans that appear to moderate the source of the noise that makes PWM fans inherently more noisy than non-PWM fans.

SPCR is about to publish some new fan tests. Perhaps those tests will be helpful in sorting all of this out.

The conventional wisdom is that sleeve bearing fans, have a short life with mounted horizontally.

I believe that MikeC accepts that conventional wisdom... but at the same time says that he has had no discernible problems like that with Nexus fans.

The problem is that you can't take the performance of a single fan and extend that to all fans of a single design. That means this conventional wisdom is hard to confirm or deny.

The one person here who has the most experience sufficient to form a reasonably valid opinion on this is MikeC. Perhaps he might chime in with his opinion.

I think you are right, i bought mine a year ago, and had a friend trying to get some and was impossible, but there are some still in the market, i posted a couple of link in my previous post. Personally i would go with Kama Flex or PLPS, either has treated me on my builds.

The Kama PWM (don`t confuse with the kama flex pwm) seems to be more widely available. An excellent fan, as smooth as a Nexus at low speeds but unfortunately it seems to be coming with a conventional sleeve bearing.



I agree, it`s hard to quantify just how much worse sleeve bearings are in the horizontal position. I`ve had sleeve bearing fans work in this orientation for more than three years without issues and I`ve also had fans that failed after a couple of years like the OP experienced. It`s hard to say but the later case seems to be the exception rather than the rule so I wouldn`t exclude sleeve bearing fans just yet.

The Nexus has done an excellent job for the last two years, so I decided to get another ($14 including delivery at Newegg) while I wait for the SPCR roundup/review on PWM fans.

Thanks to everyone for the replies,

Scott

I've had issues with Nexus and worn bearings too. I've replaced all Nexus fans with Gelid ones and have no issues to report currently.
IMO and this comes from using various fans for some time. Normal sleeve bearings are not the way to go.

Hybrid ones seem to fare better, and I've had ball bearing fans last a very long time indeed. No problems with the Noctua non PWM fans either (at the moment)
It is worth paying attention to the bearings used, for this reason I belive Nexus isn't worth looking at. They are good fans..while they last and a fairly decent price. If they improved their bearings might be worth a look again. I can't say I want to keep replacing fans on a pc build so it's somethings which is worth looking into a bit more.

IMO sleeve bearings have no place on any recommended fan list, what's the point if your quiet fan isn't very quiet after a few years use (sometimes even less)

It's interesting that Arctic have just introduced their F PWM CO dual ball bearing range of fans in 80mm, 92mm and 120mm sizes. CO = 'constantly on' and intended for 24/7 use, and as you might expect Arctic are making great play of the advantages of ball bearings over other bearing types. They claim they are '5 times more durable'. Like Noctua, Arctic are giving a 6 year warranty on their fans. There are more details here http://www.arctic.ac/en/p/detail/index/sArticle/556.

Yup I'll buy into that any maker who is willing to back up their product with a long warranty gets a thumbs up from me
One problem is well Nexus give a 3 year warranty, but I suspect if your fan still "works" they probably won't do much even if it's noisy. (if I'm wrong on that I'll stand corrected)
Only long term extended use gives a better idea of what the situation with noise and bearings are. I will say though double ball bearing fans last for ages.
Also the data some makers provide isn't consistent either. Some rate MTBF without any temperature indication. And if you're running at slower than max speed you should expect even longer lifespan.

There's a german site testing 120 and 140mm fans.

http://www.orthy.de/2011/08/354/

including comments for horizontal/vertikal use.