I bought the Gigabyte H110m-a motherboard a while back and just recently purchased the logitech z506 speaker system for gaming. These speakers are 5.1 channel, but I cannot get them to function properly on my PC. There are three cords: a green cord, which i plugged into the green "line out" port on my mobo, an orange cord, and a black cord. There are no orange or black ports on my motherboard, so i tried plugging them into the "mic in" and "line in" ports as per a post I read at the time. However, only the front two speakers worked when I tried this. When I unplugged the orange and black cords from my motherboard and the sub woofer, sound began to play from all speakers but it is very quiet from the rear speakers. I tried configuring the speakers in my windows settings, but the windows sound test would only play noises from the front left and front right speakers (not the central front speaker). Do I need a sound card with orange and black ports? I read somewhere about receivers, do I need to purchase one of those? Are the rear speakers just normally quiet? Any feedback on what's happening or what I can do would be much appreciated. Thanks!