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jvdbossc
17th July 2012, 08:09
I have been looking all around the internet and there seem to be some epic discussions going on, how to get a fan quiet.

If have came up with a voltage regulator 7805 on the 12V line and it runs great for now two (case) fans without heating. (it dims the led light of the fans as well, wich is a good thing as well)

Its for my media center wich does not contain much (hot) - hardware. I have left the cpu fan intact, since it does not get to high speed while movies are played.


Other methods where:

7V out of 12V+ and 5V+
resistor(s)
series
hook it up directly to 5V

should I expect trouble? No heat so far on the regulator as well..

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geminister
17th July 2012, 08:21
The first thing you should do is buy quiet fans. I love the Nexus Real Silent series. Getting as big fans as you can fit is also a good idea.

slk486
17th July 2012, 08:23
The only worry with undevolting the fans to make them spin slower is exactly that. If they give enough airflow, then you're fine, so obviously large fans are better suited. Some fans simply can't start when they don't get enough voltage to start - because they need the "kick", however I've never had any half decent fan do that.

In essence this is exactly what all the different fan control solutions do - how you choose to do it matters not, but psu's usually have most oomph on the 12v line.

Nexus series is good people ;)

Sent from my iPad using Tapatalk HD

bdb
17th July 2012, 09:39
Does anybody use rubber washers or double-sided foam tape to stop vibration?

I replaced the case and power supply fans with new quiet fans and then used the above to stop vibration noise

slk486
17th July 2012, 09:44
Does anybody use rubber washers or double-sided foam tape to stop vibration?

I replaced the case and power supply fans with new quiet fans and then used the above to stop vibration noise

No, I use rubber "screws" :)

WonkeyDonkey
17th July 2012, 09:46
The first thing you should do is buy quiet fans. I love the Nexus Real Silent series. Getting as big fans as you can fit is also a good idea.

+1

I've used Fractal Design fans here and also Noctua. Both work well and are very quiet.

bdb
17th July 2012, 09:58
Does anybody use rubber washers or double-sided foam tape to stop vibration?

I replaced the case and power supply fans with new quiet fans and then used the above to stop vibration noise

No, I use rubber "screws" :)


I use rubbers on my "screws"

Oge
17th July 2012, 10:03
I think that you can use a 47 Ohm Resistor. You can test it for a few minutes and see if it makes a difference. I would avoid fitting a regulator glued into silicone and, of course, it is a more expensive solution than a simple resistor. :)


Cheers,
Oge

AmiNeo
17th July 2012, 11:49
"How to get a fan quiet"...


I hear Eric Cantona is all for booting it :D

BrooksterMax
17th July 2012, 12:21
I can't answer this question from a technical standpoint but noise transfer is usually around vibration and transfer of that energy.

The bearings in the fan and the balance of the blades will contribute to that, so having a well manufactured quality fan designed for low noise will help. I know from my PS3 phat that some 3rd party fans generate noise because the bearings and balance is bad.

Otherwise using insulation/rubber to reduce transfer (or in combination) will be a good step.

Also do you need a fan? Can you get a solution without needing a fan - heatsinks/some other cooling technique?

Good luck

Damion
18th July 2012, 04:01
Like a lot of others, Papst and Nexus fans along with rubber/silicon mounting.

I use resistors for dropping fan speed. Check this site for help determining values:

http://www.blackfiveservices.co.uk/fanspeed.shtml

Buzzfuzz
18th July 2012, 08:30
Yep, for me it's Papst and Antec, I have an Antec 120mm at around 750 rpm, the back fan runs 860 and the top fan just under 1100, which the three front fans are als doing.
And that's enough to keep my beasty cool, yes even running Prime95 large FFT's or mixed bag.
I've just got the big bad Prolimatech Megahalems :-D

Even in a media center, if you have the space, go for larger cooling blocks.


Like a lot of others, Papst and Nexus fans along with rubber/silicon mounting.

I use resistors for dropping fan speed. Check this site for help determining values:

http://www.blackfiveservices.co.uk/fanspeed.shtml

Ed.D
18th July 2012, 19:58
The problem with fans is, they are designed wrong. A fan can be made much quieter by having the blades further away from any gratings or covers which is where most noise is generated.

I tested this when I built my A1200 tower. As a fix I had two fans, one was old but the same size as the other (80mm I think). I cut out the center part of the old fan and joined its housing to the newer fan making a kind of short duct. Worked a treat :thumbsup: although I've not yet added it to the tower.

Also, you can reduce noise by slowing the fan speed but it depends what you're doing if you want to chance the reduced cooling.

robinsonb5
18th July 2012, 20:12
I think that you can use a 47 Ohm Resistor.

If you do use a simple series resistor, make sure its power rating is hight enough. A quarter-watt resistor may well not be beefy enough.

I put together a simple calculator for this stuff a long time ago - you can find it here: http://www.blackfiveservices.co.uk/fanspeed.shtml

Note that the calculations model the fan as a simple resistive load, which it isn't - but it's likely to be close enough for most purposes.

Damion
18th July 2012, 22:21
I think that you can use a 47 Ohm Resistor.

If you do use a simple series resistor, make sure its power rating is hight enough. A quarter-watt resistor may well not be beefy enough.

I put together a simple calculator for this stuff a long time ago - you can find it here: http://www.blackfiveservices.co.uk/fanspeed.shtml

Note that the calculations model the fan as a simple resistive load, which it isn't - but it's likely to be close enough for most purposes.

Bookmarked your calculator years ago (see my above post) and have found it quite handy. :pint:

jvdbossc
19th July 2012, 20:15
Thanks for all the respons :thumbsup:. I've learned that I might need to look in some quality replacement fans. (not for the moment no $ )

I'll keep this solution untill some funds, then look at the quality brands mentioned here. (it also depends how much movies are played)

The resistor might be a good idea, but I had the same concern about heathing it up, since large fans.

Its just hot glue used - its not on the part that heaths a bit.