Hush Wing Store — Quiet PC cooling: 80-140 mm | hushwing-store.com
Replacing a 120 mm case fan takes about 20–30 minutes: diagnose the noise, swap the fan, then set a speed curve so the new one stays quiet.
Start by naming the noise. A low rattle that grows with speed is the classic worn sleeve bearing, which is rated for about 30,000–40,000 hours. A fast, regular tick is usually a cable touching the blades. A drone through the panels points to loose screws or vibration rather than a dying fan.
Power the PC down and unplug the fan. A 4-pin plug carries the 25 kHz PWM control line; a 3-pin plug is powered and slowed purely by voltage. Remove the four corner screws — 105 mm apart on a 120 mm frame — and lift the fan out of the case.
On narrow screens, swipe or scroll the plate sideways.
Mount the replacement with frame size and hole spacing matched; the sizes guide lists the patterns for 80, 92, 120 and 140 mm frames. Seat the screws evenly — over-tightening one corner warps the frame and recreates the drone the swap was meant to fix.
Connect a 4-pin fan to a 4-pin PWM header, or a 3-pin fan to the same header's three aligned pins. Then set the speed: a PWM curve scales the duty cycle of the 25 kHz signal (100% is full speed), while voltage control drops a 3-pin fan from 12 V toward 5–7 V.
Verify under load: the noise should be gone and temperatures should stay normal. If a rattle returns within months on a sleeve-bearing replacement, consider a rifle, hydrodynamic or ball-bearing model rated for 50,000–75,000 hours instead.
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