Higher the CFM higher the dbA?

[Bingy]

Hi is it true if the fan for a heatsink, the higher the CFM it has such as 79 CFM (cubic feet per minute) it will have a high noise, dBA such as around 36 dBA? And the opposite, if a low CFM say 20 CFM and only 9 dBA

There for the louder the fan the more cooling it does. Or the higher the CFM the more cooling it does?

Thanks

 

[Conumdrum]

Yes. Can't get by the laws of physics. But you can buy well engineered fans or poorly made ones that do bend the laws slightly.

http://www.xtremesystems.org/forums/showthread.php?t=193126

http://www.xtremesystems.org/forums/showthread.php?t=171661

 

[JohnnyLucky]

It's a general statement that is fairly accurate.

The other problem is the noise caused by air moving through, over, and around pc components. It is similar to air moving through a tree. A human being will hear the noise caused by air moving through a tree before hearing noise caused by air moving out in the open.

 

[4745454b]

For the most part yes. The faster you spin, the more noise you make. This is why 120mm and 140mm fans are so popular. They can move as much air as a 60/80mm fan, but at a much slower RPM. This means as my CFM, but at a lower noise.

There for the louder the fan the more cooling it does.

Kind of, but as Conumdrum said, not all fans are made equal. The type of fan (ball barring vs sleeve) has an impact as well. If I were buying a fan, look for one that is less then 40dba. Those tend to be pretty quiet.

 

[Conumdrum]

One of the issues with low speed large fans 140mm or larger is they do not have the pressure ability. They can't push air through the fins. Common in watercooling, maybe too much space between the blades on the fans etc. The 200mm Antec on the top of the 900 case sucks at pressure, but just to pull air outta the case with no resreictions it's great.

Lots to learn about fans, after 2 years on the forums (LOL not here) you learn a lot from pros.