Review on Super Silent Blue LED 120mm PC Case Fans 💙 - High Airflow Cooling for Desktops by CONISY (3 Pcs) by Carlos Cardoso

Shouldn't have been surprised hence the full 5 star rating but - DUH - if the 3 pin header is used to connect to the variable speed fan headers on the motherboard it stands Brightness of the LED directly related to the fan speed. I get full brightness at 80% power and above (blue tone image) and then gradually dim until they are completely off at 40% power (normal color image) and below. The fan still rotates up to 10%. Both shots were taken with the same shutter speed of the camera. Still good fans for the price. I think if you want to control brightness and speed separately. Need a 4 pin fan?