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Little Green Wire
- Thread starter Nexrus
- Start date
Does the 3pin header have just one wire coming out of it, or three? I can't tell from the pic.
Sometimes a fan will come with a normal 4pin molex and a 3pin header with just one wire (mobo fan speed control) that is optional. Sometimes that 3 pin header can also power the fan, and they're just giving you the option of where to hook it up.
Sometimes a fan will come with a normal 4pin molex and a 3pin header with just one wire (mobo fan speed control) that is optional. Sometimes that 3 pin header can also power the fan, and they're just giving you the option of where to hook it up.
No, they just give you some options to hook it up however you need to...
Nexrus said:I just bought this exact fan and it has two hook ups.. the one circled in green and red. Do both need to be hooked up? I hooked up the green one and it turns. Any help is appreciated. Thanks
Arcygenical
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The small green one is a wire that the fan uses to report it's current running RPM back to a RPM sensor (like one on the motherboard).
All it does it send some rotational speed data, and is not needed.
The 4 pin molex is all you need to power the fan, but your system will have no way of reading the fan speed (which may or may not be necessary for you...).
All it does it send some rotational speed data, and is not needed.
The 4 pin molex is all you need to power the fan, but your system will have no way of reading the fan speed (which may or may not be necessary for you...).
Nexrus said:
ok, the low down is like this. you can power the fan with either connector. Do not use them both at the same time. the small 3 pin connector is to allow you to power the fan from one of the 3 pin fan headers on your motherboard. using it this way will allow you to monitor the rpms of the fan from your your bios or any other monitoring utility you may use. the 4 pin is called molex connector. you can use this one to run the fan directly from your systems power supply, you lose the ability to monitor the fan speed but if you do nto care about that it is no big deal. just don't plug them both in at the same time...
Arcygenical
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No.
If there is only 1 single wire coming from the 3 pin connector, it will NOT power the fan.
It is ONLY the tachometer (rpm sensor). You NEED the molex to give it power, and the 3pin to sense RPM. period.
If there is only 1 single wire coming from the 3 pin connector, it will NOT power the fan.
It is ONLY the tachometer (rpm sensor). You NEED the molex to give it power, and the 3pin to sense RPM. period.
This is real simple...
Plug in the smaller connector first. If the fan spins, then it is fine. You don't need to do anything else.
If it doesn't then plug in the 4 pin molex connector. Now everything works.
As an added bonus, the three pin or smaller connector is now optional. If you have other fans that can only use that connector, and you don't have enough spaces for all of them, then go on and take that three pin connector off and plug in the fan you want to use.
Plug in the smaller connector first. If the fan spins, then it is fine. You don't need to do anything else.
If it doesn't then plug in the 4 pin molex connector. Now everything works.
As an added bonus, the three pin or smaller connector is now optional. If you have other fans that can only use that connector, and you don't have enough spaces for all of them, then go on and take that three pin connector off and plug in the fan you want to use.
NoxTek
The Geek Redneck
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<cartman> NOT SPEED CONTROL GODDAMMIT! (><) </cartman>
It's the rpm sensor wire.
Basically when you get a fan configured like this you connect the large 4-pin molex to your power supply, and then you can OPTIONALLY plug the small 3 pin connector (the one with the single wire running to it) into a fan header on your motherboard. This will allow you to monitor the fan RPM via your motherboard's BIOS (or a piece of software that will read data from the sensors like MBM or speedfan). This configuration does NOT allow you to control the speed of the fan - simply to monitor it.
These tend to throw some people off because they see that single rpm wire and 3 pin connector and don't know what the heck to do with it.
It's the rpm sensor wire.
Basically when you get a fan configured like this you connect the large 4-pin molex to your power supply, and then you can OPTIONALLY plug the small 3 pin connector (the one with the single wire running to it) into a fan header on your motherboard. This will allow you to monitor the fan RPM via your motherboard's BIOS (or a piece of software that will read data from the sensors like MBM or speedfan). This configuration does NOT allow you to control the speed of the fan - simply to monitor it.
These tend to throw some people off because they see that single rpm wire and 3 pin connector and don't know what the heck to do with it.
I have been building systems for 11 years and i have never seen one that had one single wire coming from the 3 pin header unless they were all shrink wrapped together to look like one wire. But you learn something new everyday so maybe i was wrong. kudos to those of you that have these fans and helped answer the man's question.
Blue Falcon said:<cartman> NOT SPEED CONTROL GODDAMMIT! (><) </cartman>
It's the rpm sensor wire.
Basically when you get a fan configured like this you connect the large 4-pin molex to your power supply, and then you can OPTIONALLY plug the small 3 pin connector (the one with the single wire running to it) into a fan header on your motherboard. This will allow you to monitor the fan RPM via your motherboard's BIOS (or a piece of software that will read data from the sensors like MBM or speedfan). This configuration does NOT allow you to control the speed of the fan - simply to monitor it.
These tend to throw some people off because they see that single rpm wire and 3 pin connector and don't know what the heck to do with it.
ok ok, TECHNICALLY, the small 3-pin is just the rpm monitor. It's the voltage (coming from the 4-pin) that dictates what speed the fan spins at. So TECHNICALLY you could control the fan speed without plugging in the 3-pin connector, however it wouldn't do you much good since you couldn't see the speed the fan was at already.