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Discussion Starter #1
Could someone explain to me why anyone would WANT to use the voltage step down adapter for and fan. I have corsair sp120 fans, and they come with voltage step down adapters. Why would anyone want a slower fan ? Wouldn't this make things less cool ? The only time I can even think this would matter would be for noise , and cooling doesn't matter to you, but if your gaming or care about airflow, you should forgo these items ?
 

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We all run our fans at 3000+ RPM minimum.
 

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some people like to have silent computer so I am guessing they use it for that
 

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Those adapters are supplied for users who want to reduce the sound level, but don't have the SP120s attached to something like a fan controller or mobo fan header with user controlled fan curves. (for example)
 
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Quote:
Originally Posted by Jedson3614 View Post

...The only time I can even think this would matter would be for noise...
I'm surprised you even made a thread given the mid-post revelation.
 

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Meep
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I don't get it either. With 10 7400rpm fans my temperatures go sub zero, and I can't hear my family yelling at me, what more could you want?!

Downsides are that I can't hear my PC's audio either and I'm starting to get hard of hearing. But hey, got to have those CFM's.
 

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Discussion Starter #8
Honestly I wanted to know why some of you wanted to use the step down voltage converters. I personally don't see the point if you want cooling performance, lower rpm's is most definitely going to be less effective at cooling. I never have used one, so I was wondering in what situation did any of you use them.
 

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Discussion Starter #9
Yes but in the case you use the adapter, doesn't the lower rpm have less of a impact on cooling whatever your cooling off. How much of a noise difference could it really be ? Is it worth the loss of rpm's and cooling to make it worth while ?
 

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It depends. If you have 3 fans running at full RPM and 6 fans running at 50% you (theoretically) have the same cooling. Now if you have 20 fans running at 5% imagine the silence AND the cooling...
 

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Quote:
Originally Posted by Cyclops View Post

We all run our fans at 3000+ RPM minimum.
If it can't cut fingers, it's not fast enough.

In all seriousness, it's used to reduce noise when performance is "overkill". If you only need one SP120 @ full tilt, you might be able to get away with two SP120's with the adapter.
 

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Cooling is a balancing act between temperature and noise. To some people, Temperatures > Noise so they'll run their fans at full speed. To others it's Noise > Temperature, so they'll run their fans slower at the cost of performance.
Personally I tip the scales towards my PC getting a bit hot if it means I don't have high-speed fans blowing in my ear.
 

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Discussion Starter #13
That is a great answer, and does make sense to me. I only use a few fans on my open test bench. So the extra cooling is important to me, and the noise isn't bad, so I don't really have a use for that.
 

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Quote:
Originally Posted by Gilles3000 View Post

I don't get it either. With 10 7400rpm fans my temperatures go sub zero, and I can't hear my family yelling at me, what more could you want?!

Downsides are that I can't hear my PC's audio either and I'm starting to get hard of hearing. But hey, got to have those CFM's.
Once you reach the point where your fans render you permanently deaf, you have a lot of headroom to keep increasing RPMs before other physiological effects show up.
 

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For cases, you can run fans quietly. For heatsinks, you'd run the on a PWM circuit so they'd rev up when cooling is demanded. Different rpm's for different purposes.
 

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Quote:
Originally Posted by CastleBravo View Post

Once you reach the point where your fans render you permanently deaf, you have a lot of headroom to keep increasing RPMs before other physiological effects show up.
Ugh, I have one fan with a busted bearing (I'm guessing) and if I run it full tilt it would make my entire desk shake. I just like to look at it as having a desk with inbuilt wrist massage.
 

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Low temperatures do not mean the need of high cfm or hig rpm.

Airflow and airblow are not the same thing nor do they have the same effect.

The most important parts of a cooling system are not just the coolers used or the fans supplying them, but how they all work together. Case airflow is not about how many fans we can stuff into our cases or how fast the run, but how well the flow air through the case. The key is flowing heated component exhaust air out of the system without it mixing (and heating) the cool air we are bringing into the case and to the components. If CPU cooler has 2x 140mm fans and GPU has 3x 95mm fans of airflow, we have 140sq cm of flow area on CPU and 210sq cm area on GPU. This means a minimum of 350sq cm of flow area into and out of the case to flow as much air as components. But this only works if no heated exhaust mixes with cool intake. To help avoid the mixing we usually use 20-30% more case airflow than component flow.

But don't confuse this flow rate with flow path. Setting up a case to flow properly (supply cool air to components by removing their heated air without it mixing with cool air) is probably the most overlooks and misunderstood part of computer cooling. It's not how many fans we use, but how the air flows. The ideal system airflow supplies coolers with air at or near room temperature. Most systems under heavy load are supplying cooling intakes with air 10-20c warmer than room .. and this translates to 10-20c hotter components.

I build a lot of systems, all are 2-6 case fan systems and very quiet, and all having component intake air temps within 1-5c of room at full CPU & GPU load. Often these systems have no exhaust fans. Using both intake and exhaust fans is like putting push / pull fans on a cooler. If the intake (push) fans can supply the air as intended the exhaust (pull) fans are not needed. The intakes flow air to components and on out of case.

Less fans mean less noise. If we have 5x of the same fan that a single makes 35dB, 2nd fan adds 3.1dB to the noise level, 3rd adds another 1.67dB, 4th adds 1.25dB, 5th adds 0.97dB, for a total of 42.78dB

If we use more of same fans the 6th adds 0.79dB, 7th adds 0.67dB, 8th adds 0.58dB, 9th adds 0.51dB and 10th adds 0.46dB
http://www.sengpielaudio.com/calculator-spl.htm

At the end of the day, the best way to cool a system is to be sure the components are receiving the coolest air possible .. at or near room temperature. 5th post in "Ways to Better Cooling" explains the basics. 4th post explains some ways of controlling case fan speed in unison with component fan and airflow demands. 1st post is index, click on topics of interest to see them. Link is in my sig.

Quote:
Originally Posted by ehume View Post

For cases, you can run fans quietly. For heatsinks, you'd run the on a PWM circuit so they'd rev up when cooling is demanded. Different rpm's for different purposes.
Your builds are very well done, but if case fans are being used I believe controlling their speed the same as component fans adds to the overall performance and lowers noise levels.
Quote:
Originally Posted by Loladinas View Post

Ugh, I have one fan with a busted bearing (I'm guessing) and if I run it full tilt it would make my entire desk shake. I just like to look at it as having a desk with inbuilt wrist massage.
So is the fan clicking problem adding a nice 'rhythmic sound' to your wrist massage? You know, like rain drops do.
tongue.gif
 

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Quote:
Originally Posted by doyll View Post

So is the fan clicking problem adding a nice 'rhythmic sound' to your wrist massage? You know, like rain drops do.
tongue.gif
Both of those were fixed, you know
thumb.gif
One by switching the fan, the other by switching from PWM to DC.
 

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Is it just me, or do threads like this always involve Corsair products?
 

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Meep
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Quote:
Originally Posted by ciarlatano View Post

Is it just me, or do threads like this always involve Corsair products?
Not really surprising, considering a popular brand like Corsair is quite often used by less experienced builders.
 
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