NZXT H440 Case question.

[Rhogaine]

Hi, I'm going to start this with an apology. I'm not sure if I'm posting this in the right place (probably not), but I'm new here so hopefully you can forgive the mistake.

On to the question.

I'm in the process of building in an NZXT H440 case, as the title might suggest.
I'm nearly done, I'm just connecting the last few cables. I've come across the "PWM Cable" and the "Extension Cable" on the back of the case and I'm wondering where I should connect them.

I've had a look around on the net but can't find an answer to my question specifically, hence the new post instead of reading one that's already been answered.

I'm using the Corsair H60 Liquid Cooling system with my MSI Z97S Krait Edition MOBO, and I've got the H60 plugged into the CPU Fan 1 and CPU Fan 2 as per the manual (unless I had a brain fart and read it wrong).

There's only 2 CPU fan ports on the MOBO, but the "PWM Cable" for the case wants to be plugged into a CPU fan port as well, according to the case manual.

I'm wondering:

• 
  - If it's absolutely necessary to plug the "PWM Cable" into a CPU Fan port, or if plugging it into a Sys Fan would work just as well?
  
  - If it "is" necessary, would plugging the H60 into a Sys fan suffice?
  
  - What's the "Extension" cable for? I can't seem to find a reference in the case manual.

Any and all help is greatly appreciated, and once again, I'm sorry if I've posted this in the wrong spot.

 

[Rhogaine]

I plugged the PWM cable into the CPU Fan, and I plugged the H60 pump into the System fan (because the manual said "any 3 or 4 pin").
So now they're both connected, and the PWM cable is where the manual said to put it.

Hopefully that was the right move.
Was that the right move? *nervous*

 

[Rhogaine]

It started up and is running fine.

Thanks for all the help.