Looking for a new high-CFM low-db 80 mm fan

im looking for a new high-cfm and low decibel rate 80 mm fan so that my pc doesnt sound like a diesel engine. i would want anything relatively quiet, anything below 30 db's would be fine. the only case fan i have right now is a thermal take fan that does around 40 db and avg. of 3900 rpm. any help would be great
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Vapir No2

This should suit your tastes. You can also adjust it as necessary.