Need advice hooking up z-5500's...

I have the MSI GX620 with a Realtek ALC888S sound card in it with four ports. It was advertised as supporting 7.1, so i thought I'd try to hook up my z-5500's and see what happened. I plugged the green jack into the green port and changed the effect to stereo x2, which sounded the best.

I'm wondering given the other ports, is there anything I should be doing with the orange and black jacks? There are four ports: grey, green, blue, and pink. the green has the headphone symbol, pink has the mic symbol, the other two have a circle that looks like it has a little c with an arrow pointing to it inside... have no idea what that means.

On my realtek audio manager the ports are labeled as such:
pink - center/subwoofer speaker out
blue - side speaker out
green - front speaker out
grey - rear speaker out (for 7.1)

But when I hook up the other two jacks (black and yellow) it doesn't seem to make a difference in the sound as when just the green was plugged in. How should I be hooking them up, or is the sound when I just hook up the green jack gonna be as good as it gets? My bass seems kinda weak

Here's here you can find a picture of the audio ports on my laptop (the fourth picture).



And here's a screenshot of the realtek audio manager. When I hit the little play button to test speakers, nothing comes out of the rear speakers (i've tried all sorts of different configurations of which jacks in which ports).

 

My thumbnail did not show up, I don't know why... trying again