Do 120mm fans overload motherboard header?

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Do 120mm fans overload motherboard header?

Post by lemons » Mon May 08, 2006 5:19 am


I remember reading a while ago (on the abit forums i think) that it is not advised to connect a 120mm fan to the motherboard fan header. Something to do with overloading the connections and eventually making the header stop working.

Does anyone know if this is a bit of a myth? I have always powered my fans directly from the psu, but want try my motherboards fan voltage regulator.


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Re: Do 120mm fans overload motherboard header?

Post by MikeC » Mon May 08, 2006 5:45 am

It's only relevant if you use a high speed high power fan with >.6A current draw. Put several of these on typical motherboard fan headers and you'll probably burn out the circuit, but a couple of the more typical 0.3A/12V 120mm fans silencers use will pose no problem.
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Post by lemons » Tue May 09, 2006 3:59 am

Thanks for the reply. I just what to run one yate loon 0.30A fan, so all is good. cheers bud.

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Post by cpemma » Tue May 09, 2006 2:19 pm

The motherboard manual should give you the exact limits, though it may confuse. ;) For example, my Asus manual states "The (3) fan connectors support cooling fans of 350-740mA (8.88W max) or a total of 1A-2.22A (26.64W max)...

Seems to work fine with fans well below their minimum 350mA. :D

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Post by aztec » Wed May 10, 2006 8:29 pm

I've had 2x L1A Panaflos kill the mobo headers on 2 different Asus boards. Since then...I've never used the fan headers on any boards. Except on 1 build which was using a PPC 80mm Silencer.

Obviously, you give away fan monitoring if you don't use the headers....but personally, I'd rather not use them, even if the mobo manufacturer says you can. :)

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