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- Jul 18, 2002
My current heatsink fan is 38 dba (60mm), if I replace it with a 21 dba (80mm) what would the noise difference be?
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Dba Difference
- Thread starter CrazyBorne
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You wont be able to hear the 21dba at all.... Im sure you can hear the 48dba
OP
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- Jul 18, 2002
- Thread Starter
- #3
I have a 26 dba fan, it seemed kinda loud, will the 21 dba fan be alot quieter?
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- Dunstable, uk
yes, 1/3 quieter
Generall speaking, below 30 shouldn't be audible at all.
Often, vibrations are the cause for the noise related to fans. So even the best fan at 20 db will be audible, if the hard-plastic is in direct contact with metal or other platic. Use rubber fittings instead of screws. Like these click here
A second thing to note is that decibels (1/10 Bel) is loudness at any given frequency. Since there is no real standard for measuring Db's on fans, you can never compare the Db ratings of fans between to different companies. Where Pabst may measure the highest rating in the entire human audible frequency, zalman might settle with the highest Db in a select frequency area.
I doubt this would be so, but.. you can never be too sure
Cheers, Flixotide
edit: morning typos
Often, vibrations are the cause for the noise related to fans. So even the best fan at 20 db will be audible, if the hard-plastic is in direct contact with metal or other platic. Use rubber fittings instead of screws. Like these click here
A second thing to note is that decibels (1/10 Bel) is loudness at any given frequency. Since there is no real standard for measuring Db's on fans, you can never compare the Db ratings of fans between to different companies. Where Pabst may measure the highest rating in the entire human audible frequency, zalman might settle with the highest Db in a select frequency area.
I doubt this would be so, but.. you can never be too sure
Cheers, Flixotide
edit: morning typos
OP
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- #6
Great, thanks for the info guys.
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Note that at a fixed frequency, a 3 dBA reduction cuts the noise in half. A 6 dBA noise cuts the noise in half of half, or quarters it. Etc. The A-weighted decibel (dBA) only allows comparison of noise at the same frenquency (pitch), but its weighting was made to approximate the human ear's sensitivity to different pitches. I.e., 21 dBA at a high pitch should sound just as loud as 21 dBA at a lower pitch.
Generally speaking, the frequency of the peak noise level is higher (a higher-pitch whine) for a 60mm fan than an 80mm fan, so they can tend to be less irritating.
Hmmm, 21 dBA 80mm. Unless I miss my guess, that's a Vantec 80mm stealth fan you're talking about?
Hope this helps a little. -- Paul
Generally speaking, the frequency of the peak noise level is higher (a higher-pitch whine) for a 60mm fan than an 80mm fan, so they can tend to be less irritating.
Hmmm, 21 dBA 80mm. Unless I miss my guess, that's a Vantec 80mm stealth fan you're talking about?
Hope this helps a little. -- Paul
OP
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- #8
Actually its these:
http://www.case-mod.com/store/product_info.php?cPath=28_29&products_id=69
I just gotta get some quiet fans, 40 dba is to much for me!
http://www.case-mod.com/store/product_info.php?cPath=28_29&products_id=69
I just gotta get some quiet fans, 40 dba is to much for me!
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Ah, very nice, although I read 22 dBA there for 25 CFM. You can get 27 CFM for 21 dBA from a stealth fan for $8 at the same site, although $2 is pretty tough to beat! -- Paul
-- PaulIf I'm not all wrong, you can get Pabst NGL fans, 12 dba's at 19,5 cfm... the most silent fans I know of. But they couldn't knock over a mosquito
I've chucked four of those in one of my rigs. No sound at all, and it actually brought case and cpu temps down 7-8 c's. Not all bad then eh?
Cheers, Flixotide
I've chucked four of those in one of my rigs. No sound at all, and it actually brought case and cpu temps down 7-8 c's. Not all bad then eh?
Cheers, Flixotide
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Impressive! And for the record, 4 fans running at 12 dBA combine to 18.02 dBA. A very nice figure indeed! -- Paul
OP
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How much are they and where could I purchase them? I'm trying to keep this under a very small budget. Perhaps I will mow my neighbors yard. =P
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OP
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- #15
Yikes, I was planning one getting 4-5 fans. Im not sure I can afford 4 $11 fans.
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$8 apiece at kdcomputers. I didn't quite get around to checking the other sites, though. Of course, $2 x 4 is quite desireable, and as the performance of twe two is comparable, so as long as you don't want the fan RPM monitoring, the NMB fan looks pretty good. 4 of those will sum to about 28.0206 dBA only 1 dBA higher than 4 stealth fans. (but with slightly less airflow.)
-- Paul
Of course, $2 x 4 is quite desireable, and as the performance of twe two is comparable, so as long as you don't want the fan RPM monitoring, the NMB fan looks pretty good. 4 of those will sum to about 28.0206 dBA only 1 dBA higher than 4 stealth fans. (but with slightly less airflow.)-- Paul
OP
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That's a nice find! Even has RPM monitoring! For the record, four of those would be < 24 dBA, and five of them under 24.99 dBA. -- Paul
(You should post this in cyber deals!)
(You should post this in cyber deals!
)
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Those aluminum-plated fans are pretty interesting.
Not sure whether the aluminum has more to do with heat transfer (like a heatsink, as most sites seem to imply), or with improved interface between teh air and moving blades.
For the record, the standard 80mm ThermaTake fan does 37 CFM for 2900 RPM and 30 dBA.
-- Paul
Not sure whether the aluminum has more to do with heat transfer (like a heatsink, as most sites seem to imply), or with improved interface between teh air and moving blades.
For the record, the standard 80mm ThermaTake fan does 37 CFM for 2900 RPM and 30 dBA.
-- Paul
