How do I quiet a DC Fan Clicking noise?

JohnnyWakko · Post by **JohnnyWakko** » Mon Aug 28, 2006 2:06 pm

WHY DO DC FANS CLICK?

A question that haunts many is answered by this excerpt from JMC, fan maker:

"In traditional fans, the most dominant acoustic noise is due to the fan's motor switching noise. The stator motion is a square wave that is switched on and off before and after the peak torque position. This motion causes a small amount of undulation in motor torque, producing an audible noise caused by the lower frequency commutation operation. Each small torque causes a minute contracting of the entire fan structure and results in an audible clicking noise while the fan is operating."

I have an HISx800pro AGP card with ICEQ fan on it, and it has the above clicking noise - well at least that's what I think it is. The only way I can stop the clicking is by making the fan run at 100% or 0%. Is there some other way I can stop the clicking?

Any suggestions would be appreciated.

darthan · Post by **darthan** » Mon Aug 28, 2006 3:28 pm

That type of clicking can also be caused by PWM fan slowing (as opposed to undervolting). If the card is plugged into your graphics card header try slowing it through a Fanmate or undervolting it some other way. If that clears up your noise then PWM is the problem. If it doesn't then you need to look for a new fan, I think. Well, you could try oiling it (peel off the hub sticker, put a drop of oil in the little hole).

JohnnyWakko · Post by **JohnnyWakko** » Tue Aug 29, 2006 3:40 am

Althought I have ATI Tool installed this noise was there previous to the install of the ATI TOOL. Does this mean the card itself uses PWM to slow the fan.

EDIT Found this on another forum site: "...Radeon X800 fan speed is controlled by the installed software..." Guess that answers my question on that bit.

According to the ATI TOOLdocumentation changes the PWM see here for a short reading on it:

http://www.techpowerup.com/wiki/doku.ph ... an_control

So I guess this is my problem. Is there some other way control the fan with software?

If the card is plugged into your graphics card header try slowing it through a Fanmate or undervolting it some other way.

I don't quite understand what is meant by "...is the card plugged into your graphics card header..." Can someone please explain?

Trip · Post by **Trip** » Thu Aug 31, 2006 12:09 am

What's the ICEQ plugged into?

Bluefront · Post by **Bluefront** » Fri Sep 01, 2006 2:20 am

M-Cubed sells a small device called an attenuator. It could be plugged into your system between the fan and it's attachment point on the video card. It's made for 3-pin connectors, so some wiring mods might be necessary.

This attenuator is designed to remove/reduce the clicking noises caused by the PWM. From what you describe, this is your problem. PWM is used by the video card to control fan speed......and it has a reputation for introducing extra noise, the clicking you hear below 100% fan speed. I've used these attenuators many times. They usually fix the clicking noise....

JohnnyWakko · Post by **JohnnyWakko** » Sun Sep 03, 2006 6:19 pm

Bluefront - I will look into that! Nice one!

Trip - I will have to take a closer look my friend..

On that, will a multi-fan controller device controll the fan more silently? Perhaps it is worth me getting one of these. I will have to take a close look at the card.

Trip · Post by **Trip** » Mon Sep 04, 2006 9:12 am

It's probably just plugged into your graphics card.

I think Bluefront just answered your question too

Btw, if it's not already on the recommended fans page, Bluefront's gadget ought to be added.