I'm not familiar with that board, but don't all modern boards come with just sata2 ports. Eitherway, you should plug them into sata2 ports as I assume you'll have loads spare.
You probably just have to disable the internal soundcard in the bios. I don't think soundcards need a separate power source (maybe then newer ones do?).
While you have a night to sleep on sorting your cabling out, you should probably plan how you are going to cable to ensure you have the neatest(!) and also best air flow cabling.
Pics are now mandatory. And no probs with the help. We're here to help, learn and sometimes mock!