HELP with AV8 Onboard sound!@#

Hi all :]

I've got an ABIT AV8 motherboard, which has supposedly onboard 6.1 sound (i'm sorry i don't remember which make exactly, i think ac97), so I went out today and dropped a nice amount of cash on some nice 5.1 speakers for my computer..

So I get home, and hook all the speakers into the subwoofer, then plug in all the color-coded jacks into the back of my sound card (light green, black, and light orange) and only 3 speakers work!

Only FRONT RIGHT, CENTER, and FRONT LEFT are playing sound!
I went into control panel and changed speaker setup to 5.1 speakers, and downloaded all the current drivers from ABITs website, and even tried mixing up the black connectors and orange connectors any which way possible..(i know the light green one is supposed to be front speakers, and those are fine)

I know for SURE its not the speakers, because i hooked them up to my XBOX and they were great..

Can someone please help, I'm going insane!
thanks

What kind of speakers are they? There are a couple of things that could be going wrong. First of all you could have a bad connection with your wires. If you have ever taken a headphone jack half out you will have noticed that only one speaker will work. Try fiddling with it while it is in the hole and see if you get any sound from the other speaker. Secondly did you make sure that there is not a switch on the back of the sub for 5.1 sound? It comes stock set on 2.1 and could keep your stuff from working correctly. Other than that, i am not sure what it could be. Mine works perfectly.