Gaming Headphones/Headset?

Hey guys,
Currently my gaming pc has no sound card so I usually use the output from hdmi to my television or an extension cable to the back of my motherboard. Anyway, the point is that I need a headset/headphones for gaming that are usb and maybe be able to use it with my xbox 360. Also, I have been looking at the sennheiser u320 (http://amzn.to/URpyAe) and I don't really want to go to much higher than that pricepoint. Any suggestions?

 

I am really unsure if just having digital headphones negates the need of a sound card.

However I do have the Sennheiser PC 333D headphones which are surround sound from USB. (And if anyone wants to start an argument saying they're not surround sound they are wrong, the headphones use psychoacoustic cues, it counts)

I don't know if you can still get them or how much they are but they're really lovely. 10/10 would buy again