Question CoolerMaster Masterbox NR600 - Fan suggestions/help

[Mr. Pettit]

Hey everyone,

So recently I swapped out all of the cooling fans inside of my PC since I'm going to be getting the RTX 3070 soon. I ended up getting 5 of the 120mm Noctua NF-P12 reduxes (3 intakes, rear exhaust, top-rear exhaust) and they work fairly well, however their operating noise is quite distracting. I have OCD to begin with, but even when they're idling and the PC is at normal temps they tend to make a high-pitched sort of hair drier noise. After looking briefly into the reviews for these fans and Noctua as a whole, supposedly a decent amount of people find them to be unacceptably loud. (Video here of them at around 500 RPM. The majority of the sound comes from the top-rear exhaust and the video doesn't really do the sound justice, but it's not really something I can ignore). Higher speeds result in a louder whine, so RPM doesn't really reduce it. I have no other things inside the PC that could be making the noise (I cut the CPU and GPU fans off and I have no HDDs).

Thankfully they're within the return date on Amazon, but my question is if anyone has any suggestions for quieter fans? My intention was to get two 140mms for the front, but they are situated in the case kind of odd and I figured it might compromise airflow (see here). I'm thinking if I can pretty much ditch the top exhaust as it causes more noise, but any suggestions would be appreciated.

 

[dimtodim]

Hey everyone,

So recently I swapped out all of the cooling fans inside of my PC since I'm going to be getting the RTX 3070 soon. I ended up getting 5 of the 120mm Noctua NF-P12 reduxes (3 intakes, rear exhaust, top-rear exhaust) and they work fairly well, however their operating noise is quite distracting. I have OCD to begin with, but even when they're idling and the PC is at normal temps they tend to make a high-pitched sort of hair drier noise. After looking briefly into the reviews for these fans and Noctua as a whole, supposedly a decent amount of people find them to be unacceptably loud. (Video here of them at around 500 RPM. The majority of the sound comes from the top-rear exhaust and the video doesn't really do the sound justice, but it's not really something I can ignore). Higher speeds result in a louder whine, so RPM doesn't really reduce it. I have no other things inside the PC that could be making the noise (I cut the CPU and GPU fans off and I have no HDDs).

Thankfully they're within the return date on Amazon, but my question is if anyone has any suggestions for quieter fans? My intention was to get two 140mms for the front, but they are situated in the case kind of odd and I figured it might compromise airflow (see here). I'm thinking if I can pretty much ditch the top exhaust as it causes more noise, but any suggestions would be appreciated.

https://www.amazon.com/dp/B07P998NM...5a3f7c25d3c9d8546eb8b9a758a285&language=en_US

 

[Mr. Pettit]

I'm not understanding what a case has to do with my question?

 

[Phaaze88]

however their operating noise is quite distracting. I have OCD to begin with, but even when they're idling and the PC is at normal temps they tend to make a high-pitched sort of hair drier noise. After looking briefly into the reviews for these fans and Noctua as a whole, supposedly a decent amount of people find them to be unacceptably loud. (Video here of them at around 500 RPM. The majority of the sound comes from the top-rear exhaust and the video doesn't really do the sound justice, but it's not really something I can ignore). Higher speeds result in a louder whine, so RPM doesn't really reduce it. I have no other things inside the PC that could be making the noise (I cut the CPU and GPU fans off and I have no HDDs).

It's a matter of individual sensitivity, which not everyone shares. It doesn't happen with just Noctua fans either. I have Noctua fans in my chassis and don't hear this noise at all.

If a fan is advertised for low noise(dBA), but the user is sensitive to certain frequencies(kHZ)... then the low noise becomes kind of moot.
The 'loudest' P12 Redux(1700rpm) at 25dBA, is on paper, just as quiet as the premium NF-A14 and NF-A12x25 at 24dBA. But if what's actually going on is that YOU are sensitive to the pitch of the magnetic levitation motor that the fan uses...
I believe what you're going to have to do is be willing to experiment with different fans, like ones with rifle, sleeve, or double ball bearing motors, for example.

My intention was to get two 140mms for the front, but they are situated in the case kind of odd and I figured it might compromise airflow (see here). I'm thinking if I can pretty much ditch the top exhaust as it causes more noise, but any suggestions would be appreciated.

What is that chassis?
That fan bracket is terrible for 140mm fans - that looks like NF-A14s in the pic.

 

[Mr. Pettit]

It's a matter of individual sensitivity, which not everyone shares. It doesn't happen with just Noctua fans either. I have Noctua fans in my chassis and don't hear this noise at all.

If a fan is advertised for low noise(dBA), but the user is sensitive to certain frequencies(kHZ)... then the low noise becomes kind of moot.
The 'loudest' P12 Redux(1700rpm) at 25dBA, is on paper, just as quiet as the premium NF-A14 and NF-A12x25 at 24dBA. But if what's actually going on is that YOU are sensitive to the pitch of the magnetic levitation motor that the fan uses...
I believe what you're going to have to do is be willing to experiment with different fans, like ones with rifle, sleeve, or double ball bearing motors, for example.


What is that chassis?
That fan bracket is terrible for 140mm fans - that looks like NF-A14s in the pic.

Yeah, that’s what I was afraid of. I read a tiny bit into the static pressure of fans having something to do with the pitch of the noise they put out, so I was considering getting another pair like these. That being said, I have a feeling I might just be sensitive to noctua’s SSO bearings or something.

In regards to your other question, the case is a CoolerMaster Masterbox NR600. I’ve been told that objectively 140mm tend to be better as they are more efficient than 120s, but that offset position they have has me concerned since it’s kind of blowing into the PSU shroud.

 

[Phaaze88]

I’ve been told that objectively 140mm tend to be better as they are more efficient than 120s, but that offset position they have has me concerned since it’s kind of blowing into the PSU shroud

They are, but the fan bracket's shape looks like it works against the larger fan size.

 

[Mr. Pettit]

They are, but the fan bracket's shape looks like it works against the larger fan size.

The case is marketed to handle 2 140mm fans, it’s just that weird position thing. I mean despite that do you think it’s worth giving them a shot, or should I just try again with different 120mm fans?

 

[Phaaze88]

I think you actually need to use 120mm there.
Look at the fans and where the fan blades are relative to that bracket. Do you know what happens to the air that does come into contact with the solid sections of the bracket? It bounces off.
Those small disruptions could be related to your noise problem too - I don't actually know for sure, I don't have a degree in aerodynamics.

Cooler Master didn't tool that bracket correctly for use with 140mm, even though it does support them. The air will flow more smoothly through the circular gaps with 120mm.

 

[Mr. Pettit]

I think you actually need to use 120mm there.
Look at the fans and where the fan blades are relative to that bracket. Do you know what happens to the air that does come into contact with the solid sections of the bracket? It bounces off.
Those small disruptions could be related to your noise problem too - I don't actually know for sure, I don't have a degree in aerodynamics.

Cooler Master didn't tool that bracket correctly for use with 140mm, even though it does support them. The air will flow more smoothly through the circular gaps with 120mm.

That’s a good point about the cutouts. Right now I have the 3 120mm intakes, so there’s no restricted airflow. Since the very bottom one kind of blows into the open end of the PSU shroud, do you think it even makes a difference for temperature? I mean there’s no ventilation or cutouts and it just hits the back of the PSU which is venting air though the bottom. If anything I would think it just contributes to noise.

 

[Phaaze88]

You do have a point - there's not much ventilation to speak of in the psu shroud; those holes are primarily there for installing storage drives and not air access points for the gpu.
The bottom fan can still bring some air to the psu though, even though it can already draw air from the bottom.
Whether to bottom with the bottom fan looks to be your call, though you can experiment and see what happens, whether you'll notice a difference or not.

 

[Mr. Pettit]

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.

Does this sound feasible to anyone? I also took a picture of how the intake fans sit in the case here. I took the top exhaust out and I’m considering returning it. I’m not too sure on the bottom 120mm, but it seems almost useless apart from blowing at the PSU.

 

[Phaaze88]

That moment when you stopped the fan actually spooked me for a moment!

By chance, are you using a 2nd fan on the Hyper 212 cooler?

 

[Mr. Pettit]

That moment when you stopped the fan actually spooked me for a moment!

By chance, are you using a 2nd fan on the Hyper 212 cooler?

Oh sorry about that lol. To answer your question, it’s just the one stock fan on the cooler that I showed in the recording. I’m not using any other fans on it.

 

[Phaaze88]

It was my own fault. I cranked the volume up because I wasn't hearing anything beyond a certain 'rubbing' sound, like if I were to rub my hands together lightly. Well, that's what it sounds like to me.
You're probably right about the fan bearing.

To answer your question, it’s just the one stock fan on the cooler that I showed in the recording. I’m not using any other fans on it.

Gotcha.
I couldn't tell from the video, but was curious about it.
Some fans make an audible buzzing when used as pull on a heatsink. I found that out testing NF-A14, A15, and F12s as pull on the NH-D15S heatsink.
The fan blades aren't contacting the heatsink, and I'm no aerodynamics engineer, so all I can call it is some kind of turbulence - even knowing that's not the right term for it.

 

[Mr. Pettit]

It was my own fault. I cranked the volume up because I wasn't hearing anything beyond a certain 'rubbing' sound, like if I were to rub my hands together lightly. Well, that's what it sounds like to me.
You're probably right about the fan bearing.


Gotcha.
I couldn't tell from the video, but was curious about it.
Some fans make an audible buzzing when used as pull on a heatsink. I found that out testing NF-A14, A15, and F12s as pull on the NH-D15S heatsink.
The fan blades aren't contacting the heatsink, and I'm no aerodynamics engineer, so all I can call it is some kind of turbulence - even knowing that's not the right term for it.

Yeah, I wasn’t too sure what it was exactly. If you listen closely to the recording there’s still a rattle present even when I stop the fan with my finger. That’s the old exhaust fan that came with the case which came with the case. It was pretty flimsy and kind of crappy.
You can hear that sort of rubbing noise start up when I let the fan go again. The recording doesn’t do it justice but maybe you’re right about the turbulence. I know very little about fans but if the bearing is offset, maybe the airflow is choppy through the top of the case? I mean the sound I was hearing when I started the post isn’t really similar to the CPU fan, but that seems to be what is causing the issue.

 

[Phaaze88]

If you listen closely to the recording there’s still a rattle present even when I stop the fan with my finger. That’s the old exhaust fan that came with the case which came with the case. It was pretty flimsy and kind of crappy.

Yes, I heard it.
That's typical of preinstalled fans. Manufacturers get those for real cheap; can't expect good quality, only that they do their job.

 

[Mr. Pettit]

Yes, I heard it.
That's typical of preinstalled fans. Manufacturers get those for real cheap; can't expect good quality, only that they do their job.

Oh alright, just checking because I posted on it in the past on the Linus forums and someone claimed to not hear any noise out of the ordinary. I was considering just getting rid of the entire CPU cooler and getting one that has a metal mount like this, but I think it might be overkill.

 

[Phaaze88]

The heatsink isn't broken, so no real need to replace it, but a fan or 2 instead.