[SOLVED] Where should I connect the CPU fan wire?

[Jacob 51]

My CPU fan has 3 pin connector and the motherboard has 4 pins connector. I understand that one pin is for speed control, which is not there
but which pin should i connect to which one

 

[drea.drechsler]

4 pin fans are PWM controlled fans. three pin fans are DC controlled fans.

Your motherboard expects a DC control for the CPU fan since it has a 3 pin connector. Most PWM fans, though, will operate on a DC control so go ahead and use it. The connectors are keyed (there's a plastic flag on the motherboard header that will slip between two tabs on the fan connector to locate it) so they will install correctly whether 3 pin or 4.

But it's also likely the motherboard will drive it with a constant +12V though with no adjustments for any other voltage output. That's the case with my Asus board, if that's the case with yours many coolers come with a 'quiet' adapter that drops voltage for that situation. You can also attach it to a case fan header if they allow adjustment of the DC voltage to control fan speed.

BTW...a 3 pin, constant +12V output header is correct for a liquid cooling pump since they're supposed to operate at full speed all the time.

 

[Jacob 51]

4 pin fans are PWM controlled fans. three pin fans are DC controlled fans.

Your motherboard expects a DC control for the CPU fan since it has a 3 pin connector. Most PWM fans, though, will operate on a DC control so go ahead and use it. The connectors are keyed (there's a plastic flag on the motherboard header that will slip between two tabs on the fan connector to locate it) so they will install correctly whether 3 pin or 4.

But it's also likely the motherboard will drive it with a constant +12V though with no adjustments for any other voltage output. That's the case with my Asus board, if that's the case with yours many coolers come with a 'quiet' adapter that drops voltage for that situation. You can also attach it to a case fan header if they allow adjustment of the DC voltage to control fan speed.

BTW...a 3 pin, constant +12V output header is correct for a liquid cooling pump since they're supposed to operate at full speed all the time.

But which pin on the CPU fan socket should I leave open? The one on the left or the right?

 

[drea.drechsler]

But which pin on the CPU fan socket should I leave open? The one on the left or the right?

there's only one way without forcing it

just make sure the tab on the motherboard slips into the little slot in the connector and it will work. Like this:

https://landing.coolermaster.com/faq/files/cooling/kA090000000MrmX_4.jpg

This shows 4-pin fan connector on 4-pin header, just imagine the 4th header pin missing and the connector hanging over, so in this picture it would be the one on the right.