I am building my first computer and I am running into a few small problems

The one I am having now is that the names on the pins on my dfi lanparty expert dont match the names on my nzxt lexa case

The ones on the mobo are

Pin 13 speaker data
Pin 15 N.C.
Pin 17 ground
Pin 19 speaker power


and the plugs on my case are

Ground
L-ret
R-ret
L out
R out
MIC power
MIC in

I need to know which ones to plug where


Thank you

No one will answer you until you have created a proper sig. That information will tell us what you are puting together to build your computer. You see I am having difficulty figuring out what you are talking about. I think the first line of your sig is
DFI LanParty UT Sli-DR Expert/BIOS

Also add lines for your case, PSU, ram,cpu, HDD, Optical devices, Floppy, etc,,,,
Then we can look at your manual and see what you are talking about. Kind of talk from the same book, so to speak. Thank you and a Hearty Welcome.

I changed my sig I hope that helps with the confusion

The one's you pointed out on your case(above) are for audio. Look in the manual of both case and mobo again.

I belive you have found the header for the digital audio out (optical).

The pins you want to connect to are located on the Karajan audio module.
Look it up in your manual.

thanks it is on the karajan audio module

I was looking at the front panel pins