Have you tried the Logitech G430? A pretty decent sound for just 99$.
Unless you are a audiophile i would suggest just getting the G430. Comes with a 7.1 USB sound card and it's also possible to use it without the USB.
If not you can try to get ATH-AD700 from amazon & just get a modmic with it. Might be a better option since it's on sales right now. However, it's a open can but since you're using it for gaming it will be a better choice! [/URL]
You don't really need a soundcard unless you are using some really high end gears else i don't think you should waste the $.
Hopefully you'll do some research first before buying any!