Wiring Diagram Computer Fan. Most stand-alone adjustable thermostats ie. Note that Chassis and CPU fans may use either 3-pin or 4-pin power connectors.
Wiring Dual Cooling Fans. Wire color usual 1. With the help of this third wire a monitoring circuit can see the rotation.
Chassis and CPU fans may use either 3-pin or 4-pin power connectors.
4-pin connectors are usually used by CPU fans with higher power consumption. Fans and on-board fan headers are backwards compatible. This is based on the draw from the fans if the fans are larger and draw more than 15 amps each its recommended to install a second relay kit as shown below. Chassis and CPU fans may use either 3-pin or 4-pin power connectors.
