Four fans to single PSU connectorChoice of fan operating speed (5V and 12V connectors) A simple way of increasing the number of fan connections and providing control over fan speed, which can make high speed noisy fans significantly quieter. Attach the fans to the connector with yellow/black wires for +12V supply or with red /black wires for reduced speed +5V supply. - Connects four fans to the PSU - Speed reduction for two fans - Choice of 5V and 12V connectors