Want to read more answers from other tech-savvy Stack Exchange users? Check out the full discussion thread here. Have something to add to the explanation? Sound off in the comments. Source: Three Wire and Four Wire Fan Connectors Note: When connecting a three wire fan to a four pin fan header, the fan is always on there is no fan control.Ī four wire fan connecting to a four pin fan header:Ī four wire fan connecting to a three pin fan header: The four wire connectors are for processor fans with higher power consumption.Ī three wire fan connecting to a four pin fan header:
The three wire connectors are for small chassis fans with lower power consumption. With this type, fan speed is typically controlled by increasing or decreasing the voltage over the power wire.Ī four pin connector is a little different than the three pin connector since it has the extra (fourth) wire used for controlling and sending signals to the fan, which likely has a chip on it that tells it to slow down or speed up (in addition to the other wires the three pin connector has).Ĭhassis and processor fans use either a three wire or four wire connector. The signal wire measures how fast the fan is moving without any controls for the fan’s speed. I tried connecting the wires to the motherboard manually in different configurations, but the fan will not spin. I stripped off the connector and now Im left with blue,black,red and yellow wires. SuperUser contributor Homey_D_Clown_IT has the answer for us:Ī three pin connector is basically power (5/12 volt), ground, and signal. I opened my laptop for cleaning, and in the process I managed to break my laptop fan 4 pin connector. What is the difference between three and four wire CPU fans? The Answer What is the difference between three and four wire CPU cooling fans (besides the obvious answer of one wire)? SuperUser reader RockPaperLizard wants to know what the difference is between three and four wire CPU fans: