Which Headset to Buy for FPS Games

I'm a novice at really anything audio related and was hoping for some help on which headset to but. I can spend up to $150 and have been looking at the Steelseries Siberia v2 USB, and the Steelseries Siberia v2. I've heard that the new Steelseries Siberia v3 is coming out soon but I don't know the release date so they're not my first choice. I don't have a sound card but my Gigabyte Z77X-UD3H motherboard has VIA Audio HD. I would rather have a surround sound headset so I'm not sure if I should buy the cheaper ones and get something to make the audio 7.1. Any help would be extremely appreciated.

Thanks is advance.

Also not really hardware related but what frequency are gunshots usually on? I noticed that gunshots are way to loud and I can't hear anything else over them. 

the Steelseries Siberia v2 are ok for games ...but they a crap for music

That's fine I don't listen to a lot of music.

I am a Global Elite on CS: GO and I use the Kingston HyperX Cloud headphones :) They are 64 ohms though so u might wanna get an amp with it too :)

Take a look at this :) http://www.pcgamer.com/the-best-gaming-headsets/