[Rowana]

I've removed the 12v DC processor fan from my old dead computer as I have an alternative use for it, the fan that is. I was surprised to find 3 leads.
These are coloured black, red and yellow. I'm asuming black is negative, red is positive, but what is the yellow lead for, and can I just ignore it?

The fan is an akasa with a sticker on the side AK821 if that is relevant.

[Advertisements]

Hi Rowana,

Correct with the Red & Black. A yellow or white wire Is connected to a sensor which you can ignore.

[iammykyl]

Hi Rowana,

Correct with the Red & Black. A yellow or white wire Is connected to a sensor which you can ignore.

[Rowana]

Hi iammykyl,

Thanks for the welcome and also for the information.

I see you are in Brisbane, I hope you weren't too close to the recent floods. What with that, the earthquake in NZ and the terible tragedy in Japan, I'm sometimes glad I'm in Scotland!

Thanks again
Jim

[Digerati]

You MIGHT be able to ignore it, but I wouldn't. If the motherboard's (BIOS/Chipset) hardware monitor does not sense a CPU fan, it might, depending on how the BIOS Setup Menu is configured, fail to boot. So while this fan is now a spare, and you can use it elsewhere, if it is ever going to be used by a CPU again, I would take care not to damage it.

[Rowana]

The fan is from an old dead computer which has had various bits removed for other projects. I'm going to use it for a non-computer related project, so it will never be used in another computer.

[iammykyl]

You MIGHT be able to ignore it, but I wouldn't. If the motherboard's (BIOS/Chipset) hardware monitor does not sense a CPU fan, it might, depending on how the BIOS Setup Menu is configured, fail to boot.

I should have qualified my reply thus, A yellow or white wire Is connected to a sensor which you can ignore providing you are not using it as part of a computer build.

I see you are in Brisbane, I hope you weren't too close to the recent floods. What with that, the earthquake in NZ and the terible tragedy in Japan, I'm sometimes glad I'm in Scotland!

Thanks for your concern. We live in the South Eastern side of Brisbane and had some local flooding due to rain but mot effected by the river flooding. Quite terrifying to just see the havoc let alone experiencing it. As for Scotland, beautiful but far too cold in the winter. Give me the Sun anytime.

[Digerati]

A yellow or white wire Is connected to a sensor which you can ignore providing you are not using it as part of a computer build.

Ummm, that's not necessarily true either. First, there is no standard color coding required by the ATX Form Factor standard. The sensor wire may be white, yellow, blue, or just about any color that is not used by the other two wires.

Also, it may not be up to the user whether he uses it or not. As I noted above, the BIOS may look for a connected fan during boot/POST. But regardless, the CPU fan is so critical, it should be used, and not ignored.