I wanted to upgrade my stock part cooling fan to a pair of noctua 40mm fans and when I did a test run they barely push any air through the ducts compared
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Noctua NF A4x20 40mm CPU Cooler Fan 12v 5v PWM/FLX Cooling Fan Chassis Radiator Replace fans|Fans & Cooling| - AliExpress
Quiet 12V NOCTUA Fan on 24V Creality Ender 3 - YouTube