Installing all fans on CM 690 II Advanced

Putting together my new rig today. One question:
My Asus P7P55D-E mobo has 6 fan sockets. They are:
4 pin CPU fan
4 pin chassis 1 fan
3 pin chassis 2 fan
3 pin pwr fan

Now, I have my CPU fan all hooked up and ready to go. Now, I have three 3 pin fan connectors, and only two 3 pin sockets on the mobo. I hooked it up so it all works, but my rear fan has nothing to plug into, as closest fan socket (chassis 1 fan) is 4 pin.

I also have some devices that look like this:
Is there some way to hook up my 3 pin fan to the 4 pin chassis 1 fan connector?
Is this mysterious wiring harness the answer to my problems?
Help me out! Thanks!
5 answers Last reply
More about installing fans advanced
  1. Yep! link some of your fans into molex.
    I have 6 mobo fan sockets 3 are free still.
    5 chassis fans 4 linked in molex one on mobo socket.
    HSF is push/pull and i use 2 mobo sockets.
    Btw i'm no expert on this matter and i'm sure my configuration could be improved with some expert input.
    All my case fans were prewired and powered up through my psu molex.
    How many fans are you trying to hook -up?
    Btw the top set-up is an Antec 902.
    On my CM 690II Basic it came with an intake and rear exhaust no problems.
    I've added side and top exhaust also.
    If i recall the only mobo sockets i used were for the cpu cooler and the side fan.
    Everything else i powered with molex.
  2. How exactly do I do that?

    I plug the 3 pin plug from the adapter into the mobo. Ok. Then I plug a psu molex adapter into the female molex adapter. This leaves me with two fans to hook up and one male molex adapter connected to the PSU and mobo. What now?

  3. What psu do you have?mine came with 8 4 pin adapters
    Cuz if you get everything in position right you can easily daisy chain 4 pin connections.
    I have a 4 pin lead coming into the bottom of my 902 with two adapter heads and i can attach two case fans to just one head.
    Get a 4 pin led out and up to your top exhaust and use the same one for your rear exhaust, that will take care of the exhaust.
    Get one to your intakes.
    I'm horrible at explaining this sorry.
    And my CM 690II is at the cottage.
    Really the only mobo fan connections will be your cpu cooler and any additional auxilary fans like a side/bottom mount or the small one on the back of the mobo.
    And any additional gpu cooler fans.
    All your main case fans can be powered by your psu.
  4. I gather you have plugged one 3-pin fan into the PWR_FAN pinout. Although that is not what it was designed for, on some mobo's it works, running that fan at full speed always.

    But your remaining dilemma is having a 3-pin fan and an unused 4-pin mobo pinout - I'm guessing Chassis_1. The way these pinouts are built, you can plug a 3-pin fan into a 4-pin port, and it will only fit one way, with the 4th pin not connected. As far as the wiring goes, the result probably will be that the fan only runs at full speed, not under control by the mobo. A 4-pin output supplies full 12 VDC at all times to the + pin on the pinout, and then a 4-pin fan uses the PWM signal on the 4th pin to achieve control of power flow from the + pin through the fan motor. A 3-pin can can't do that, so it will run with that full power and speed. SOME mobo's actually can be manually set to control a 3-pin fan on such a port - they do it by changing their operation and varying the DC voltage on that + pin, just the way a regular 3-pin pinout does.

    I looked through your manual and cannot find any specific statements about the fan control capabilities. It does not indicate that you can manually set any 4-pin output to operate like a 3-pin. It does not specifically say you must not mix fan types. So, go ahead and plug it in there.
  5. All sorted! Ended up plugging the 3 pin into the 4 pin as Paperdoc suggested, and we have victory.

    And I also learned how to use the molex adapters! Dual knowledge!

    Thanks y'all!
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