I love my Turtle Beach HPA2 head phones, can't recommend them enough.  They use a pass over to connect to your 5.1 sound card and only uses a USB connection to power the mini-amp that comes with it.  The 5.1 is true 5.1 surround sound and the sound quality is excellent for games and very good for movies and music.  
ack-ack
OMFG.  I saw these mentioned by a Ack Ack and others on the boards and when I needed a headset, I decided to pick up a set to replace the ones my son "more or less permanently borrowed". 
I can't believe how much better things sound - it's literally like hearing some of my favorite music again for the first time. 
And to think I've spent as much as 40 dollars or so on a binaural "nothing really special" headset when I need one the last couple of times - I can't believe how much better these sound for just a bit more. 
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