New comp sound issue

hello i got a new computer with a i5 cpu and everything works great. i recently got a 5.1 surround sound headset and i plugged everything in to the right color connectors and went into my control panel to set up the 5.1 surround but only the front speakers work when i do the sound test and not the surround and bass. i used all the connectors with my ipod and they all worked so im not sure what i need to do to get it to work on my computer.

this is the headset that im trying to use http://www.newegg.com/Product/Prod [...] 6826235007

and my motherboard is http://www.newegg.com/Product/Prod [...] 6813131404

What does you the speakers do without the headphones plugged in? My experience is when I plug my headphones in, my standard speakers don't work. I'm not running 5.1 Surround Sound but it still could play a part.