Static vs Airflow what would cause most wind noise?

[rn2]

I have a 140mm Be Quiet Silent Wings 3 PWM case fan (1000rpm) strapped to my GPU and as it is the quietest fan I have ever used I don't really want to swap it up over wind noise but would a static fan create the same noise. My case is quite big and spacious and not full of hardware, it is also completely silent apart from this. The fan is pointed upwards and I can hear the noise start as the fan gets to 50% speed. It isn't the fan itself, it seems to be the noise of the wind going through the spacious case, despite only being a 140mm fan it does throw a lot of air out as I can feel it when I ramp it up to full speed and the back of my case is directed behind my desk and about 4 feet away.

https://ibb.co/GCQVghd

The heatsink is huge and the fan is more than adequate to cool the GTX1070.


I doubt if there is a fix and I will have to get used to it but thought I would ask. I did not notice it in my old case but the case had louder fans on it so now I notice it, I guess it is the vicious circle of trying to get a silent case.

On further inspection I can hear the noise increase with the rpm increase and emitting from the fan/heatsink itself. Could be because the fan is strapped right onto the heat sink (surpised at only 500rpm though) so I may try adding some type of spacer in between if I can like a hollowed out 140mm fan to see if that fixes it.

 

[8 Pack]

Protein shakes cause far more wind noise!!!

 

[rn2]

Protein shakes cause far more wind noise!!!

Haha good one.

I must admit I have a high sensitivity to sounds, mostly low frequencies. I suffer with really bad tinnitus and it causes me to not sleep much. This combination increases stress, anxiety and depression and also results in over active neurotransmitters firing off in my brain. I am in a constant state of flight/fight and it is not very nice at all to live with.


I found a video of a similar fan but the 120mm version and you will be able to hear the sound that is emitting from my own fan which annoys me, in the video you can hear the obvious fan noise but at near exactly 5 seconds in there is another more harmonic noise which acompanies it. If you have good ears you will be able to hear it. That is my level of sensitivity to certain noises. I am not sure what is causing that specific noise though.

https://www.youtube.com/watch?v=6fMvzHDu3WU

having a new silent case hasn't helped as I a pick up these sounds now that I wouldn't in my old noiser case.

 

[doyll]

Protein shakes cause far more wind noise!!!

But do they cool any better?

Try a spacer between fan and cooler fins. This often makes a dramatic difference in fan sounds.

Considering Silent Wings 3 fans have some of the best (if not the best) sound profiles available I would be surprised if you can find a nicer sounding fan.

Is it the case vents that might be making the airflow noise you are hearing?

There really isn't 'static pressure' and 'airflow' fans. All fans have static pressure and airflow ratings. The difference is higher static pressure rated fans can overcome more airflow resistance and maintain a good airflow. Also, as fans' speeds are reduced so are their static pressure and airflow ratings, and considering most of us don't run our fan at full speed very often if at all, having a higher static pressure rating means we can slow them down more with them still being able to maintain enough airflow for our needs. Hope that helps.

 

[rn2]

Thank you for your reply .

Like you said I'd not find a better sounding fan. My experience with noctuas were not the best. I think the be quiet 3 are the best built too. The back of the computer is full of mesh vents which obviously allow the sound to be heard.

The noise seems to be normal and nothing that is out of the ordinary. It's just that i pick up on it as it's the only noose I hear from my case now.

I've been thinking about it a lot and I think my own cure for this is to cover up the vents with sound proofing. Add a second low rpm 140mm intake fan to the front for extra cooling to counteract any extra heat generated and attach a small directional duct to the exhaust so the air and noise from inside the computer is directed away more.

 

[Meddling-Monk]

Just curious @rn2 which Noctua fans did you happen to have a bad experience with?

Incidentally, I've also silenced my system lately (compared to before at least, not truly silent yet), and I can confirm that so long as you have good hearing, you will keep picking up on noise you didn't hear before during each stage of quietening the system short of going full passive, as you become accustomed to each sound level you reach. Personally, I was never really that bothered about the silence level until I went over to one of my kids to help diagnose their GPU issue, and found the system from OCUK to be so much more quiet than my rig, that I went about researching into silencing it down. (The CPU had a be quiet HS/Fan combo, but didn't look into it further, just marvelled at how much more quiet it was than my AIO and their STOCK fans... ).

 

[rn2]

Just curious @rn2 which Noctua fans did you happen to have a bad experience with?

Incidentally, I've also silenced my system lately (compared to before at least, not truly silent yet), and I can confirm that so long as you have good hearing, you will keep picking up on noise you didn't hear before during each stage of quietening the system short of going full passive, as you become accustomed to each sound level you reach. Personally, I was never really that bothered about the silence level until I went over to one of my kids to help diagnose their GPU issue, and found the system from OCUK to be so much more quiet than my rig, that I went about researching into silencing it down. (The CPU had a be quiet HS/Fan combo, but didn't look into it further, just marvelled at how much more quiet it was than my AIO and their STOCK fans... ).

I think I prefered my old system (only for the loud woosh of the intake fan on it which masked pretty much everything else ha). I think if I buy some sound proofing and the duct I would imagine that I spent about £100 or more on quieting my system. I still have 3x Noctua NFb9 redux fans which I will be selling, they were quiet but didn't get rid of the heat enough on my GPU.

As for the Noctua fans I used they were NF-F12's I ordered two and returned both and they have it fitted to their NH-U12s cooler (rma'd that fan for a second fan and both were causing a lot of vibration in the case). All of the NF-F12's were pretty poor. all sounded terrible against any type of mesh.

Arctic sale pretty silent fans (as you can see in the pic I use them) but they don't last long before they start ticking or humming, luckily not audiable with my seating location and sytem position.

I will proceed with my plan of putting sound proofing over the rear vents and installing a drectional duct for the exhasut fan, luckily the case is pretty good for air flow and I can install a second 140mm low rpm fan at the front. the gpu heat sink I use is from an arctic twin turbo cooler and it's huge so temps are kept pretty low anyway on that.

I have ordered some 12mm thick flame retardant acousitc foam as it will be the only sound barrier so I ordered the thicker one https://ibb.co/dm4kYfs and this https://ibb.co/BLr0wbX the duct tubing is from America £30 all together bearing in mind I will keep this case for years to come it should hopefully work, the ducting will be good to blow the warm air around a corner and direct sound away too.

I'll post an update with a picture when it's done .

 

[doyll]

Thank you for your reply .

Like you said I'd not find a better sounding fan. My experience with noctuas were not the best. I think the be quiet 3 are the best built too. The back of the computer is full of mesh vents which obviously allow the sound to be heard.

The noise seems to be normal and nothing that is out of the ordinary. It's just that i pick up on it as it's the only noose I hear from my case now.

I've been thinking about it a lot and I think my own cure for this is to cover up the vents with sound proofing. Add a second low rpm 140mm intake fan to the front for extra cooling to counteract any extra heat generated and attach a small directional duct to the exhaust so the air and noise from inside the computer is directed away more.

Sound dampening will limit airflow. and that kind of ribbed ducting creates turbulence over the ribs with resulting noise.

I suggest moving your rear exhaust fan (I assume that is now the source of your noise) to front intake. Use no exhaust fans. Fans with a good pressure rating as intakes don't need exhaust fans. Using intake and exhaust fans in a case is like using push/pull on a cooler or radiator. Only difference is sometimes exhausts fans can help create airflow currents/channels in different areas of case than only intake fans. What case do you have?

I would remove the grill mesh on back vent and if you want a grill there use one of the wire ring grills like in below image

I have found removing mesh grills from back and bottom vents both increased case airflow and lowered noise.

 

[rn2]

Sound dampening will limit airflow. and that kind of ribbed ducting creates turbulence over the ribs with resulting noise.

I suggest moving your rear exhaust fan (I assume that is now the source of your noise) to front intake. Use no exhaust fans. Fans with a good pressure rating as intakes don't need exhaust fans. Using intake and exhaust fans in a case is like using push/pull on a cooler or radiator. Only difference is sometimes exhausts fans can help create airflow currents/channels in different areas of case than only intake fans. What case do you have?

I would remove the grill mesh on back vent and if you want a grill there use one of the wire ring grills like in below image

I have found removing mesh grills from back and bottom vents both increased case airflow and lowered noise.

The noise is only coming from the gpu fan when it speeds up. I can't remove the rear mesh and I don't need to anyway as the exhaust fan is quiet. I am aware of how anything put in front of the vents will limit airflow weather it is sound proofing or not but I explained how I would counteract that with an extra intake, air is getting pushed up and out as it is so I am not worried about blocking the vents. I will let you know how I get on with my adjustments. The case is a Pure Base 600 and with the case fans set on the lowest voltage speed my gpu only hits 60oC at high usage thanks to the huge heat sink on it.

 

[Doug2507]

I put a pair of nf-af12 on my hybrid rad. Never been so impressed by a fan as these, super quiet and push a fair bit of air through. Just wish they had black version out and weren't 30 quid a pop!

 

[rn2]

Update if anyone is interested . I Covered all vents at rear of computer with 6mm sound proof foam, didn't do much to hide the annoying frequency of the Be Quiet GPU fan but looks pretty neat at least ha.

I did perform a test though on the computer with the sound proofing on the back of the computer to se how it will handle the heat with the vents being covered up. The case is a Be quiet 600 case with a 140mm 800 rpm Arctic intake fan and a 120mm 600-1350rpm arctic exhaust fan (Both set at the lowest of the 3 case controller speeds). The game was set to 100% GPU usage and the Be quiet GPU Fan reached 802rpm with the temperature stable at 64oC, I was very impressed with this, the GPU heatsink back plate helps too as you can see it's pretty big https://ibb.co/GCQVghd.

I will probably just try to get used to it as like somebody said earlier in the thread "I won't find a quieter fan" and I seem to be picking up the same frequency from the exhaust fan too anyway. Seems to be normal wind/turbulence noise that I am becoming sensitive to. Best just to ignore it I think, could be also due to mild hearing loss causing me to pick up on other frequencies more.

I won't post again here with a fan related/noise related thread, thanks for your help and input guys.