ATX 12v connector question.

[Maximilian]

I have a corsair cx400 with 2x4 pin ATX 12V connectors and a gigabyte H77 board with 1x4 pin ATX 12v connector.

Usually board these days have an 8 pin ATX 12v connector. Does it matter which of the ATX connectors from the PSU i use? They both seem fit although the shape of the plugs is slightly different.

To clarify, this is the plug im talking about:

This is what ive got:

 

[imagoon]

Normally you plug the keyed one in first (the squared peg on the left) if you only have 2 x 2. If you have 2 x 4 you plug in both. However they are all 12v (4 yellows) and grounds (4 blacks) so they work interchangeably. Keyed one is "more correct" though.

If you have a meter you might want to check in case it is an EPS connector.