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My ASUS P8Z68-V PRO/GEN3 motherboard has the following fans:

  • 2 x Chassis Fan connector(s) (1 x 4-pin, 1 x 3-pin)
  • 2 x Power Fan connector(s) (3-pin)

The fan cable connector has three pins (and it already has molex attached to it).

What I know until now is that (correct me, if I am wrong):

  • The connector (with molex) can be connected to power-supply
  • The connector (without molex) can be connected to motherboard (if it supports) to regulate the fan (without having the fan to be on all the time)

What should I connect my case fan to, if I want to connect it to the motherboard? Please note that this is my first build.

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up vote 9 down vote accepted

Well, all three options are possible.

The chassis fan option is definitely the best option - it will do speed control, and will keep the fans running at the required speed. Where possible, this is the best option. Use the chassis fan controllers first

The molex/fan connector connected to a molex connector will have the fan running at full speed all the time, unless you have a fan controller. You'll notice the 'converter' you have only has two pins, since computer fans gracefully degrade down with lesser wires - 2 wires are fixed speed, 3 wires have PWM for speed control and 4 wires also do speed feedback. This will as such, run your speed controllable fan at a single speed, controllable by voltage

As for pwr_fan - various sources source 1 source 2 say that it won't control the fan speed and Its proper use is for monitoring PSU fans where supported. If you have more fans than chassis fan connectors, you could presumably use this as it should be possible to power a fan off it, however. Practically this would be preferable if you didn't want to use a molex connection specifically for fan power, but its not a replacement for a proper chassis fan supply.

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Just splice the wires to a connector which does connect using ample electric tape or similar adhesive, if you cannot find an adapter which I assume is your problem.

More importantly the amperage will be enforced by the power supply first and the components on the motherboard second so there is little to no danger of any harm. The third connector just gives more 'Juice' to the fan and allows it to spin at a higher rate.

You could likely connect your cellphone to the same connector and charge it, I have done it before and incorrectly and it has ruined a battery or two.

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I said this is my first build. If you don't want to answer, just don't answer. I am not asking you. I am asking those who want to help. – user122530 May 17 '12 at 3:34
@anon_anon is right--this is a properly formulated question. There is no reason to close it as "not a real question". Furthermore, your answer requires more skill than the OP has, as indicated by the fact that this is his first build. – bwDraco May 17 '12 at 4:01
@JourneyMan, nice response! – Jay May 17 '12 at 4:29
Funny thing is i have (possibly an older revision) of the very same case, and was wondering the exact same thing when cleaning out the system its in. And had the same chassis fan vs molex connector issue, when i was putting it back together.I had to look up the pwr_fan bit tho. – Journeyman Geek May 17 '12 at 5:29
My answer was still right. – Jay May 17 '12 at 11:34

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