Quick question about 3-wire fans

[tjwilly]

I want to use a proc/heat sink fan as a cooling fan elsewhere. I have an extra 3-wire fan available. My question, is the Blue wire. If I am not mistaken, red=12v, black=gnd, and blue=??. I really don't know what to do with that. My thought was it is used for data reporting to the bios, but I really don't know.

If you are curious, I am building a small gps-pc for my car. And I need some cooling in a external drive bay I built.

Can I just snip it and use power and ground for constant velocity cooling?

Thanks

 

[kobaj]

I want to use a proc/heat sink fan as a cooling fan elsewhere. I have an extra 3-wire fan available. My question, is the Blue wire. If I am not mistaken, red=12v, black=gnd, and blue=??. I really don't know what to do with that. My thought was it is used for data reporting to the bios, but I really don't know.

Yep, it reports the rpm of the fan back to the motherboard that way if it goes down to 0 the mobo can alert you and tell you the fan died.

If you are curious, I am building a small gps-pc for my car. And I need some cooling in a external drive bay I built.

Can I just snip it and use power and ground for constant velocity cooling?

Thanks

Ya, its perfectly fine to just cut it off.

 

[tjwilly]

Yep, it reports the rpm of the fan back to the motherboard that way if it goes down to 0 the mobo can alert you and tell you the fan died.



Ya, its perfectly fine to just cut it off.

Great. Thanks for the timely reply!

Best wishes.

 

[elitehacker]

Why don't you use a cheap two wired ones? Why would you want to waste one?