Noctua LNA resistor ratings?

Oscuro

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Discussion starter · #1 · Apr 14, 2013

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Wondering if anyone has found the specifications of the resistors in the Noctua LNA or ULNA adapters, as I am contemplating throwing one in to wrangle my EFB0912HHE that's running exhausting my computer at 4000rpm.

I know people have stacked a few fans on one adapter before, used higher amp fans, etc...but this fan is rated at .64 amps....and I don't really feel like having a bbq with my computer, or having a resistor puke itself or grenade on me.

 

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TELVM

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#2 · Jul 7, 2013

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Black LNA: 50 Ω

Blue ULNA: 81 Ω

http://www.silentpcreview.com/article1020-page5.html

Judging from size I'd say wattage is 0.5~1 W .

 

ehume

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#3 · Jul 7, 2013

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Why not write to Noctua and ask about their current resistors? They have several kinds, as you can see in this review. And even then, there are LNA/ULNA resistors I did not see because I don't have those fans (e.g. -- 40mm, 60mm, etc.). I have a 92mm fan on the NH-L12. It has yet another resistor.

Maybe Noctua will tell you the Ohm numbers.

 

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TELVM

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#4 · Jul 7, 2013

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I've got a dozen or so resistors from NF-B9, NF-P12 & NF-P14s. Measuring with multimeter all blacks are ~50 Ω, all blues are ~81 Ω.

May be the newer (A14, A15) Noctua models come with different value resistors. It's dead easy to find, anybody with one of these fans can read the resistor with a multimeter.

BTW to help tweaking fan speeds with resistors & voltages there is this handy online Fan Speed Calculator.

.

 

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TELVM

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#5 · Jul 8, 2013

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Unlike other Noctuas the NF-F12 PWM comes with only a resistor wire, labelled "LNA NA-RC6".



I've measured it at 81.4 Ω. So it's functionally identical to the classic blue ULNA.

If and when I lay hands on other models of Noctua fans I'll post more resistor readings here.

 

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TELVM

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#6 · Aug 15, 2013

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The NF-S12A FLX comes with two resistors:



LNA 'NA-RC10' = 51Ω
ULNA 'NA-RC12 = 147.5Ω

 

doyll

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#7 · Aug 15, 2013

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+REP for that. Good info to have.