How to connect the chassis fans

  ened 17:08 PM 05 Mar 13

I have Corsair Obsidian 550D which comes with three fans. The psu is a CIT 750W.

There is only one connection on the mobo and I can't see any on the psu. So how can I fire up the other two fans?

  Bris 19:33 PM 05 Mar 13

Here is a selection of adapters. This assumes that you have a spare molex connector from the PSU and that the fan plug is of the correct type for the adapter. The other thing to consider is the fan voltage. I assume that the case fans are 12 volt so the adapter needs to be pick up the 12 volt supply from the molex connector (some pick up the 5 volt supply).

Hope this helps.

  Bris 19:39 PM 05 Mar 13

This one appears to have 2 x 5 volt connectors and 2 x 12 volt

  Number six 00:55 AM 06 Mar 13

The exhaust fan will connect to your mobo. The two intake fans are powered by one standard molex connector from your psu.

  ened 05:50 AM 06 Mar 13

"The exhaust fan will connect to your mobo"

The fan connector is three pin but the mobo connector is Four pin. It still fits on there but does this matter.

Bris Thanks for the links. The only thing is I can't see if they are what I want. I think I shall see if I can get some splitters in Maplins.

  Chronos the 2nd 08:38 AM 06 Mar 13

What motherboard have you got? If it is an ATX size mobo then there will be more than 1 fan header even the next size down, M-ATX, will give you more than 1.

As for fitting a three pin into a four pin header you will notice that the connection on the fan will have two small plastic ridges these slide either side of the plastic upright on the 3/4 pin header on the motherboard.

Can I suggest that your power supply is not a decent make and although it says 750w I very much doubt you will get that much. you should never buy a cheapo PSU, if they fail they can cause a lot of damage.

  ened 09:35 AM 06 Mar 13

Chronos the 2nd I have the solution to this.

I am going to put the psu in my old machine and stick the present one in the new machine. I was going to do this anyway but have now made a decision,assisted by your 'cheapo' comments, to switch this one off and swap psus.

I have discovered another header by the cpu fan one. In addition my other psu is modular and I have a three pin connector which came with it.

Many thanks for all your help.

  Chronos the 2nd 10:14 AM 06 Mar 13

Can you tell me what your motherboard is?

  ened 11:43 AM 06 Mar 13

Thanks for your help I have just ordered:

This should be resolved now but the mobo is : Asus P8Z77-V LX

  Chronos the 2nd 12:45 PM 06 Mar 13

Just had a look at your mobo and you are right only two fan connectors which is rubbish.

but anyway I would have gone for this Fan Splitter and swapped the fans for 4 pin PWM which would give you some control over the speed via the BIOS.Less speed less noise. Of course you could get a fan controller and stick it in a spare optical drive bay. I have just got my hands on one of these. Prodigy. Which will sit nice in one of my builds.


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