Jump to content

Choosing the right fan based on db(A) and its airflow

JoeTheProgrammer
By JoeTheProgrammer
in Cooling
 Share
Go to solution Solved by ZetZet,

sound adds up, if you have 20 fans that make no sound turn them on together and they will be loud as heck. Impossible to answer these questions in numbers.

Posted

How many dB(A) could a PC fan have so that average human would not be able to hear it or to be (very) quiet?

How much airflow CFM does a 120, 80 and 60mm case fan need to have to be effective?

What is the typical RMP to get this much airflow with various fan sizes?

Link to comment
Share on other sites
Link to post
Share on other sites
Posted
  • Solution

sound adds up, if you have 20 fans that make no sound turn them on together and they will be loud as heck. Impossible to answer these questions in numbers.

Location: Kaunas, Lithuania, Europe, Earth, Solar System, Local Interstellar Cloud, Local Bubble, Gould Belt, Orion Arm, Milky Way, Milky Way subgroup, Local Group, Virgo Supercluster, Laniakea, Pisces–Cetus Supercluster Complex, Observable universe, Universe.

Spoiler

12700, B660M Mortar DDR4, 32GB 3200C16 Viper Steel, 2TB SN570, EVGA Supernova G6 850W, be quiet! 500FX, EVGA 3070Ti FTW3 Ultra.

 

Link to comment
Share on other sites
Link to post
Share on other sites
Posted

Fan specs are generally unreliable. Look at benchmarks and reviews instead.

If you ever need help with a build, read the following before posting: http://linustechtips.com/main/topic/3061-build-plan-thread-recommendations-please-read-before-posting/
Also, make sure to quote a post or tag a member when replying or else they won't get a notification that you replied to them.

Link to comment
Share on other sites
Link to post
Share on other sites
Posted

@WoodenMarker Could you recommend some site which specializes in this? I've done quick google search which show me some blog posts that could be helpful but no benchmark site like let's say http://www.futuremark.comfor GPU/CPU.

That's because fan reviews are a bit more strenuous. The good ones are usually done by some very generous people with too much time on their hands.  :wub:

http://www.overclock.net/t/1321074/tator-tots-big-quiet-120mm-140mm-fan-round-up

http://www.overclock.net/t/724577/the-well-dressed-megahalems-65-fans-and-112-setups-56k-warning

If you ever need help with a build, read the following before posting: http://linustechtips.com/main/topic/3061-build-plan-thread-recommendations-please-read-before-posting/
Also, make sure to quote a post or tag a member when replying or else they won't get a notification that you replied to them.

Link to comment
Share on other sites
Link to post
Share on other sites
Posted

Dude listen. I'm gonna give it to you straight no chaser. The hard truth is that if you want the best sound with the best performance, noctuas are the way to go. Your questions don't need to be answered. Just trust noctuas will get the job done and you will be beyond satisfied. 

I just ran CPU Burner for 10 minutes with my NH-D15 and temps never maxed, and I still couldn't hear the fans. 

I hate the look of noctuas but dude man they're worth it. 

 

Sorry for being so adamant 

 

I feel like I should still answer your question. >25 dbA and you'll hear your breathing over whatever is in the case. Some companies lie about noise levels (Zalman cough CNPSx12) but noctua and be quiet are true as a rainbow. 

 

You should be more focused on static pressure for rads, heatsinks, and filters. CFM is just for case airflow. 30 CFM will get the job done. Noctua has a fan that achieves that at 6.0 dbA. Yeah thats right. Only six decibels. You will not hear that thing at max. Then again twice that cfm will actually get some air flowing, not just a supply of fresh air. If you want to be able to stick your hand in your case and feel air moving against it, you'll compromise some noise, but noctua still has a 60 cfm with only 20 decibels. 40 decibels is where you start to hear things. Just keep that in mind. 

Good luck good sir. 

I wish you the best. 

I really want to build an oil-immersed PC  ^_^

Link to comment
Share on other sites
Link to post
Share on other sites
Posted

@Jeremykin Thanks for the tips.

I once had as many questions as you did... I get it man. 

Also... RPM really isn't a factor in performance. A really good blade design will perform at low rpm with good performance, whereas a bad design with high rpm (which is naturally louder) will basically match up with the good blade design.. You should do some research. Find out which fans Linus likes, or Jayztwocents, or barnecules.. All very reliable youtubers (LInus is the best what what) Anyways, I think Linus likes noctuas, Jay corsair, and idk about barnecules. But watch some reviews, and look at test statistics. NOT THE STUFF THE COMPANIES TRYING TO SELL TO YOU SAY!! - That last point is essential. I got ripped off with a cooler that claimed 24 max decibels and it was the loudest in my case.. 

 

Anyways, best of luck to you sir.  I hope your endeavors with your PC bring you happiness. 

 

I really want to build an oil-immersed PC  ^_^

Link to comment
Share on other sites
Link to post
Share on other sites
Posted
  • Author

Thank you, I hope that in the end I'll make a good decision. But few things changed and I've decided that I am not going to buy my new build now which means that I won't be needing my new fans either. I am confident that with all the information and benchmark graphs I will be able to choose the right ones.

PS: Yes It's quite obvious that good blade design and bearing of the fan are the most important factors. Not to mention size.

Link to comment
Share on other sites
Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share
Go to topic listing Cooling

×