Maximum PC

Hello, I am working on my first build specs here:

-case: hafx full tower case
-cpu: Intel i7 3770k
-heatsink: (fan that comes with i7)
-gpu: GTX 680 evga 4gb
-motherboard: Asus P8z77-v le plus
-power: Corsair AX750
-ram: patriot viper 16gb 2x8 DDR3

I am stuck now at the wiring stage of the build and I have a lot of questions.

Firstly I am unsure of how to attach the cords from my power supply:


to what appears to be a 8 pin hole on the motherboard that powers the cpu (hole labeled EATx12V):


Secondly I don't know if having these extra two pins from the power cord just hanging off my gpu is alright (cord labeled PCI-E):


Thirdly the only sata power cable from the power unit that reaches both my disk drive and hard-drive has 4 sata power
outlets on it. Is it okay to only use some of them and have others plugged into nothing?:


Lastly I'm having some issues with how to connect some of the case wires to the motherboard. I do not know what this wire
is because its only label reads "1394" although it resembles a usb in apearence:


Here you can see these led wires from the case but the motherboard manual fails to properly diagram the are where they
plug in (pic 1 is the wires pic 2 is the motherboard):



Thank you for any help given! Also if you know any helpful resources or where I could find someone
knowledgeable about building computers that would be appreciated as well. If this information is not
sufficient then I can make a video but it will take awhile to upload. My internet isn't great. Also sorry
about the large images if they are too big I can fix them but I thought having them large might help a bit.

You only need one, but you should plug in both.


It is, otherwise it wouldn't be detachable.


Yes.


That's for Firewire interfaces. Don't plug that into your USB header, otherwise you may blow out the USB controller if you plug in a FireWire device.


Are you sure the one already in the PWR header is for the switch? Otherwise, you don't need those per se, they just turn on the power-on LED on the case.

So yeah, if it's not plugged into anything, it's fine.