Dude, i know what i am talking about; Logitech g35 is the way to go, you cannot find real 7.1 at that price, in fact Tiamat is the only real 7.1 headset, i've tried both of them and there is almost no diference.
The logitech g35 uses an usb connector and that is why you don't need any sound card, this headset is abolutly amazing, you got a slight better mic than the tiamat and the sound is almost identical
Hope this helped you
I think G35 is best way to go. Logitech makes good headsets in my opinion but remember that Sennheiser is very good audio brand aswell they have few very good 7.1 headsets too. You shouldn't even think real 7.1 Headsets cause they have terrible Audio quality and remember human has only two ears so why would you need more than 2 speakers?