Noctua P12 - loud at 900rpm, or faulty?

daveconn41 · Post by **daveconn41** » Mon Jun 01, 2009 7:15 am

Hi all -

Picked up a Noctua U12 cooler with it's included P12 fan. Bios is showing RPM as 900~ with the slower resistor used. Unfortunately it's easily the loudest part of my machine, absolutely drowning the other noise sources (isolated hdd, 80mm psu fan). If I combine the two Noctua resistors, it becomes slightly less audible though not much better - but more importantly it doesn't spin up on boot.

Just wondering if I've got a bad fan, or the P12 is a "quiet" high CFM fan in the sense it's quiet for the amount it pushes... Either way, seriously unimpressed so far.

neumein · Post by **neumein** » Tue Jun 02, 2009 4:24 am

It's possible you got a dud fan, happens from time to time.

From personal experience, the P12s have a "unique" sound, which can, depending on circumstances (background noise, how and indeed where they're mounted) become rather annoying. I live near-ish a major road, and the general background noise drowns out my noctua @ 7v. But later on whilst gaming at night, when things quiet down a bit, there is a bit of drone coming from the p12. Given that I like to run my hardware @ bleeding edge, I have to put up with some noise, so I may be a bit biased

daveconn41 · Post by **daveconn41** » Tue Jun 02, 2009 7:00 am

Hmm - I have it mounted to the U12 with the isolation strips (not sure how much these actually do). Not impressed at all though - compared to old Nexus 120mms I've had this isn't close to quiet, nevermind silent. Just ordered a S12-FLX potentially against my better judgement, but we'll see.

Going to try and get hold of a Zalman Fanmate too just to see how far I can tweak down the rpm of the P12, as the in-line resistors supplied seem to be a miserable failure so far... Failing that, I'm hoping ducting the U12 to a back case vent with a S12 on it is enough to cool my CPU.

mgarl10024 · Post by **mgarl10024** » Wed Jun 03, 2009 4:58 am

Hi,

If you suspect it of being faulty, why don't you send it back?
You might get a replacement which could last longer and wouldn't irritate you as much.

Hope that helps,

MG

Post by **NeilBlanchard** » Wed Jun 03, 2009 5:20 am

Hi Dave,

How would you describe the sound it makes? Does it make the same noise if you hold it in your hand, or if you open the side of the case?

N-K · Post by **N-K** » Wed Jun 03, 2009 9:20 am

I have the same fan as a case fan.
It was far too loud with one of the adapters and it didn't even start with the other.
I connected it directly to the PSU. It runs @5v so it's about 600rpm.
It is not that loud any more but it definitely makes some noise.
I was sure it was my HDD vibrating but the noise stopped when I stopped the fan. It seems to have quite a lot of bearing noise.

I'm slightly disappointed. I thought this would have been a better fan.
I have only few air intakes in my case so I thought this would have been a perfect fit.

Zenphic · Post by **Zenphic** » Wed Jun 03, 2009 2:19 pm

Yeah, the P12 makes a decent amount of noise at anything above 700RPM. It works well at 5V though.

daveconn41 · Post by **daveconn41** » Fri Jun 05, 2009 1:06 am

NeilBlanchard wrote:Hi Dave,

How would you describe the sound it makes? Does it make the same noise if you hold it in your hand, or if you open the side of the case?

I'll investigate further over the weekend - need to rebuild the machine with tidied cables etc, tho I can't imagine this is effecting the fan's noise.

From memory, the fan's pitch is kind of a muted whine - it builds after the fan's spun up for a few seconds or so. Using the same fan speed cables that came with it on the freebie lain-li fans resulted in a much more growl-y, gutteral sound but still the same kind of pitch and percieved sound level.

daveconn41 · Post by **daveconn41** » Mon Jun 15, 2009 1:07 am

So, after buying a Fanmate and playing with the P12 - I can confirm it's excellent at 800rpm. Really quiet, easily drowned out by my decoupled HDD's ambient buzz, and my system is as close to silent as I'm going to get it with moving parts.

Unfortunately - and this is a big issue IMO, when you're buying expensive fans - the Noctua in-line resistors are just rubbish. Whether the fan is off a molex or system header, they get the RPM nowhere near quiet, nevermind silent. I bought an S12FLX from Noctua after, as an intake fan - both out of morbid curiosity and that it's marketing fit my purpose, and on it's "600rpm" lowest connector it's easily the loudest in my machine. I have no doubt a fanmate or fan controller would resolve this.

Irritatingly, running two of the Noctua resistors in-line stops fan spinup on boot, which a Fanmate doesn't.

danimal · Post by **danimal** » Mon Jun 15, 2009 9:16 am

are they resistors, or are they zener diodes? time to break out the multimeter...

i have 3 of the p12's as case fans, but i haven't tried using the supplied voltage control plugs... when i screwed a p12 down into one of the p180 plastic fan frames, it changed the noise characteristics.

for $19 each, these fans are o.k.

Shamgar · Post by **Shamgar** » Wed Jun 24, 2009 12:17 pm

I'm considering getting a NH-U12P but have long been concerned about the P12 fan. Given all the controversy over the Noctua fans, it seems like such a waste to buy an excellent heatsink like the NH-U12 only to be let down by a troublesome (but supposedly high quality) fan. I would just end up with an expensive heatsink. If they offered it without the fan at a ~$20-30 reduced price, it would be a better deal. Somehow, I don't think that will happen.