Noctua NF-P12 redux - Loud operating noise

[Mr. Pettit]

Hi everyone,

 

So recently, I decided to upgrade the fans in my case (I have a CoolerMaster Masterbox NR600). I went with 5 Noctua NF-P12 redux-1700 PWM fans (3 intakes, the rear exhaust and one in the top-rear). Recently I've been noticing that there's an aggravating moan/whine to the fans when they're running, even when I'm idling on the desktop. I've tried loosening the screws a bit and I bought anti-vibration pads to no avail. Messing with the RPM doesn't seem to make the noise subside regardless of speed, though it does get louder when playing games to the point of irritation. It seems to be coming from the exhaust fans in particular, and given the lack of any sound dampening in this case it's very hard to ignore (attached video is when they're idling. I have them on a splitter and they run at ~550 RPM)

 

 

Any help would be greatly appreciated

[Bombastinator]

That’s not a lot of speed for a 120mm, for a generic 140mm it would be maybe 50rpm into audible? It would depend.  If it didn’t change with vibration dampeners it’s not vibration transferring to the case.  Noctua generally doesn’t do enlobal bearings so the balance won’t be as critical.  They’re also generally really good about removing casting flash.  Maybe some got left somewhere?  Best I got

[Mr. Pettit]

27 minutes ago, Bombastinator said:

That’s not a lot of speed for a 120mm, for a generic 140mm it would be maybe 50rpm into audible? It would depend.  If it didn’t change with vibration dampeners it’s not vibration transferring to the case.  Noctua generally doesn’t do enlobal bearings so the balance won’t be as critical.  They’re also generally really good about removing casting flash.  Maybe some got left somewhere?  Best I got

If it was a different pitch I would be fine with the noise (obviously all fans make noise, I just read about the reputation of noctua), but frankly it’s very irritating when I’m using my computer for work or class and even more so when playing games.
I know very little about fans, but I was recommended these particular ones. Two things I’ve read (maybe someone can verify this) is that these particular fans are more suited as CPU coolers, and that sleeve bearing fans aren’t made for horizontal fan mounting. I tried looking into it and apparently noctua uses a special type of bearing, but that’s all I can think of.

[Bombastinator]

8 minutes ago, Mr. Pettit said:

If it was a different pitch I would be fine with the noise (obviously all fans make noise, I just read about the reputation of noctua), but frankly it’s very irritating when I’m using my computer for work or class and even more so when playing games.
I know very little about fans, but I was recommended these particular ones. Two things I’ve read (maybe someone can verify this) is that these particular fans are more suited as CPU coolers, and that sleeve bearing fans aren’t made for horizontal fan mounting. I tried looking into it and apparently noctua uses a special type of bearing, but that’s all I can think of.

I can help a little with the sleeve bearing thing.. noctua doesn’t use just sleeve bearings. They use FDB bearings.  They actually bought the patent for the original one.  It’s how they got their rep.  FDB is a modified rifle bearing.  So a sleeve bearing but with a groove in it to distribute the lubricant but also microscopic wave patterns cast into the spindle to distribute the lubricant even better.  There was some scientist that worked for years developing the best computer fan bearing that he thought could exist and that was the design he came up with.  It crushes all the ball bearing types.  It’s reliable from any angle and has a longer working life than anything but enlobal (maglev) bearings which DONT work from every angle.  There are bearings nearly as good made by other manufacturers but there aren’t anything better. A straight up sleeve bearing isn’t always bad.  They do need to have horizontal spindles though so the lubricant gets distributed or they go bad fast. FDB doesn’t need that.  they squirt the lubricant everywhere no matter what position they’re put in.

[Demonic Donut]

I have P12 redux fans on my GPU and they aren't noisy. The only sound problem I have with my Noctua fans are if they are mounted close to a restriction in pull. For example as a case intake fan. They make a horrid buzz over 50% or so. I had to space my side intake fans to make it stop. I find my Noctua fans to be pretty quiet, other than gentle air noise, under 60% speed.

 

It's hard to tell anything from your video clip though, so I'm not sure what noise (abnormal or not) you have. Can you pull a fan a verify the same noise without it mounted? If you can, start a recording with no fan, then step the rpm up a bit at a time so we can hear it better. You can also try rotating the fan as it runs to see if vertical vs horizontal etc does anything. Is it all the fans or just one?

[Mr. Pettit]

40 minutes ago, Demonic Donut said:

I have P12 redux fans on my GPU and they aren't noisy. The only sound problem I have with my Noctua fans are if they are mounted close to a restriction in pull. For example as a case intake fan. They make a horrid buzz over 50% or so. I had to space my side intake fans to make it stop. I find my Noctua fans to be pretty quiet, other than gentle air noise, under 60% speed.

 

It's hard to tell anything from your video clip though, so I'm not sure what noise (abnormal or not) you have. Can you pull a fan a verify the same noise without it mounted? If you can, start a recording with no fan, then step the rpm up a bit at a time so we can hear it better. You can also try rotating the fan as it runs to see if vertical vs horizontal etc does anything. Is it all the fans or just one?

I’ll try to record it tomorrow morning. The noise I’m talking about it that higher pitched “ring” over the normal whooshing noise of the fan operating, kind of like a hair dryer. The recording doesn’t do it justice, but it’s very distracting and quite unpleasant. From what I can tell, the majority of the noise is coming from the horizontally mounted exhaust.

 

The intakes are dead quiet and only produce the noise of air moving, so I know it’s not the normal operation noise for the fan in general.

[LogicalDrm]

If you verify it's the fan by itself and not anything else in the system, start RMA with Noctua. The fans have 6 year warranty.

[Mr. Pettit]

So a little follow up,

 

I was going to record the fans out of the case but after putting my ears up to the intakes, it looks like they make the same noise as the exhaust.

 

Despite this, most of the noise I’m hearing is coming from the top exhaust, with a bit coming from the rear as well. Maybe the fact that they’re facing outwards is making the operation noise more obvious? I contacted noctua just to verify that this noise is normal, and I’m thinking at this point it probably is. I read a couple of reviews where people claim that they’re just generally unacceptably noisy for them. I got them on Amazon and they’re still within the return window thankfully.

 

If that’s the case, does anyone have any suggestions for alternative fans? The case I have is fairly high airflow from what I’ve read, but I’d like to keep the noise down to a minimum if possible. 

[WoodenMarker]

Make sure the noise is from the fans by stopping them completely.

The noise seems similar to that from hdd's. 

[Mr. Pettit]

On 10/12/2020 at 10:52 PM, WoodenMarker said:

Make sure the noise is from the fans by stopping them completely.

The noise seems similar to that from hdd's. 

Oh that’s interesting. I don’t have any HDDs though, just two SSDs.

 

So a little update to this all:

As several have suggested and Noctua support mentioned too, I removed the top exhaust fan out of the case and listened to it operate in my hand from different angles. It sound okay outside the case I think, and in the process I may have found the issue.

I have a coolermaster hyper 212 black edition CPU cooler. The fan on that is actually rattling due to a bearing I think, and someone explained that they don’t really make quality fans. I figured that was fine, and I’m in the process of getting a replacement via RMA. I put my ear to the heat sink, and it sounds like that is rattling around from the fan. I’m pretty sure that the noctua fans are kind of resonating it around the case (hence why I was thinking the case fans all made the noise). Other than that, the mounting plate for the heat sink is made out of cheap plastic, and I’ve installed it several times to the point where it’s a little worn out, so that may be contributing to the problem. I have tinnitus so it’s kind of hard to source out the problem even when isolating the noise, so that’s just my best guess.