Scythe 120mm S-Flex SFF21E is not really quiet
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Scythe 120mm S-Flex SFF21E is not really quiet
I just got a Scythe SFF21E (the 1200RPM 120mm S-Flex). I read a lot of recommendations for it claiming that it's quiet. It's not a noisy fan, but I wouldn't call it quiet. It's significantly noisier than the Lian-Li LI121225bl-4 which is the fan that comes with Lian-Li cases. I ran both the Scythe and the Lian-Li at 12V - I didn't try undervolting.
I believe it vibrates more than the Lian-Li as well since it managed to vibrate the metal grate that was screwed to it (it's a rear exhaust fan), while my Lian-Li fan doesn't do that.
The Lian-Li rotates at 1300RPM, by the way.
The only theory I have to explain this is that maybe the fan itself it quiet, but I hear the airflow. Based on my inaccurate "hand test" (place the hand behind the fan...) the Scythe pushes significantly more air than the Lian-Li (even though the specs suggest the opposite).
I believe it vibrates more than the Lian-Li as well since it managed to vibrate the metal grate that was screwed to it (it's a rear exhaust fan), while my Lian-Li fan doesn't do that.
The Lian-Li rotates at 1300RPM, by the way.
The only theory I have to explain this is that maybe the fan itself it quiet, but I hear the airflow. Based on my inaccurate "hand test" (place the hand behind the fan...) the Scythe pushes significantly more air than the Lian-Li (even though the specs suggest the opposite).
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Yes, it isn't quiet at 1200rpm, but try it at 600rpm - excellent.
The other reason I like it is that it can run at very low voltages. Speedfan tells me that mine are now running at 410rpm (very lowest setting on the Zalman MFC1). I also have the 800rpm version and that stalls at anything below 600rpm (but is also very quiet at 600rpm).
If you want quiet at 1200rpm, then maybe a 1600rpm version undervolted may do the job.
The other reason I like it is that it can run at very low voltages. Speedfan tells me that mine are now running at 410rpm (very lowest setting on the Zalman MFC1). I also have the 800rpm version and that stalls at anything below 600rpm (but is also very quiet at 600rpm).
If you want quiet at 1200rpm, then maybe a 1600rpm version undervolted may do the job.
Sure you can undervolt it and reduce vibrations but it's probably covering up a mounting issue.
Vibration noise should be a non-issue with proper mounting, meaning that you should focus more on the actual noise the fan makes.
You should soft mount your fan or anything with moving parts otherwise you're leaving a lot to chance.
Vibration noise should be a non-issue with proper mounting, meaning that you should focus more on the actual noise the fan makes.
You should soft mount your fan or anything with moving parts otherwise you're leaving a lot to chance.
No. It is normal for 120mm fans to become audible at around 700rpm, and it's only due to the amount of air they are pushing at that speed. The S-FLEX is very quiet below that speed, and still pretty quiet above, and that's why it is a recommended fan.echn111 wrote:Sure you can undervolt it and reduce vibrations but it's probably covering up a mounting issue.
Yes if he is complaining about vibration noise. And saying the S-FLEX has more vibration than the Lian-Li fan.Modo wrote:No. It is normal for 120mm fans to become audible at around 700rpm, and it's only due to the amount of air they are pushing at that speed. The S-FLEX is very quiet below that speed, and still pretty quiet above, and that's why it is a recommended fan.echn111 wrote:Sure you can undervolt it and reduce vibrations but it's probably covering up a mounting issue.
There should be "zero" (or close to zero) vibration noise if properly mounted.
p.s. I actually agree with what you're saying, but we're talking about two different things.
Excessive vibrations can be a sign of a damaged fan, even the best fan can be suffer damage during shipping/handling.
Are you sure they are running at a similar speed? Though unlikely, it is possible that Lian Li revised the specs of the case fan. My Lian Li came with a very good 1000rpm fan for example.
Are you sure they are running at a similar speed? Though unlikely, it is possible that Lian Li revised the specs of the case fan. My Lian Li came with a very good 1000rpm fan for example.
If you have vibration noise at 1200rpm, then you've got a problem. You can certainly cover up your problem by reducing rpm's to 600 or below therefore covering up inadequate soft mounting or a real problem with your fans, but that's all you're doing: covering up a problem. At 1200rpm, you "should" have audible fan noise (unless your case is well sound proofed), but you "should not" have any vibration noise that is transmitted to the case and clearly audible. I suggest you remount your fans and fix them and check if your fans or damaged as the previous poster suggests.Modo wrote:I was also talking about vibration noise. I have two 1200rpm S-FLEX hard-mounted in my build, and they are completely inaudible at any speed below 650 rpm. If there is vibration noise present, it only shows at higher speeds, where there is airflow noise already (so the source becomes irrelevant).
You need to softmount every fan in a Lian-Li aluminum case, or it will reverberate like no other.visualguy wrote:It turns out that my 120mm Lian-Li fan also vibrates its fan guard on occasion. I can't be 100% sure if it's the guard or the back of the case. The case is Lian-Li PC-A7110b (which is aluminum).
The fan is mounted with the usual metal screws.
Mass loading the side panels wouldn't hurt, either.
Vibration is very hard to trace. I'm pretty sure now that the offending party is the the metal strips (not sure what they're called) which cover unoccupied PCI slots. The top is screwed in, but the bottom can move back and forth a little bit and make noise as a result of vibration.JaYp146 wrote:
You need to softmount every fan in a Lian-Li aluminum case, or it will reverberate like no other.
Mass loading the side panels wouldn't hurt, either.
I was going to try to put something there to stop the PCI slot cover from having any play, but instead I just undervolted my fans so that they don't cause vibration. The fans are also much less noisy now, of course.
I actually prefer steel cases to aluminum cases for a number of reasons, but I just wasn't sure which full-tower steel case was good when researching this. I don't actually like the Lian-Li that much, and not just because it's aluminum. The design of the case is such that removing things like some of the fans (front bottom) or the top rear hard drive cage is major surgery, including in some cases having to remove the motherboard to access the screws - a really bizarre design from that perspective.
I'm still looking for a good full-tower steel case.
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I just checked it again and the lowest it will reliably start (maybe that is the problem) is 585rpm. I can run it lower once it has been started.blackworx wrote:Interesting. Mine was fine doing 360rpm @ 6V.victorhortalives wrote:I also have the 800rpm version and that stalls at anything below 600rpm
It is on a Fanmate 2 running from a 90W Pico PSU. I haven't measured the actual voltages. (I also had the same problem when running it from the ZM-MFC1 /Corsair HX520 combination)
On my other PC, the 1200rpm fans run at 417rpm and 424rpm from a ZM-MFC1 running from a Corsair HX520.
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1200rpm is high for any 120mm fan if you want silence. Lian-Li fans (the black ones) are especially good for low vibrations and relatively low noise, but don't seem to push at much air for the same speed, so for a true comparison, cut the speed of the Scythe a bit. I would also agree that the difference between <900rpm and 1000+ with an S-Flex is considerable.
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Strangley enough, I'm on the same boat as you.
I have the LianLi A71. I think it's a very similiar case to the A7710 that you have.
I wanted to replace the stock Lian-Li fans. They're very quiet at 12v, pushing a moderate amount of air. Through the advice of a friend I've chosen to try the Slipstream 120mm @ 1200rpm. It pushes out a lot of air, but it vibrates a lot more and I can hear the motor noise. But at 1000rpm using a resistor it's almost silent and not audiable at all.
Can anyone recommend good 120mm intake & exhaust fans? I will have some obstruction before the intake (filters and grille), what's the best fan to suck in enough air?
The exhaust I will have no obstructions, so I guess I could go for something really quiet but I don't want to lose out on the ability to draw out heat either.
I have the LianLi A71. I think it's a very similiar case to the A7710 that you have.
I wanted to replace the stock Lian-Li fans. They're very quiet at 12v, pushing a moderate amount of air. Through the advice of a friend I've chosen to try the Slipstream 120mm @ 1200rpm. It pushes out a lot of air, but it vibrates a lot more and I can hear the motor noise. But at 1000rpm using a resistor it's almost silent and not audiable at all.
Can anyone recommend good 120mm intake & exhaust fans? I will have some obstruction before the intake (filters and grille), what's the best fan to suck in enough air?
The exhaust I will have no obstructions, so I guess I could go for something really quiet but I don't want to lose out on the ability to draw out heat either.