What model is your laptop and soundcard? If it is 5.1 capable through the jacks you're talking about you should have an application provided with the laptop that changes the outputs to whatever speakers they're assigned to. From what it sounds like to me you have a line out/in a mic in and a headphone in. When you stick a jack into each of them you either get a menu asking what you've plugged in - Centre &Sub, Rear R&L and Front R&L. Or just run an app and it'll assign them to what you've plugged in, but generally laptops are not 5.1 capable and some of those that are (mine included in this one) output the 5.1 signal through the optical cable, which in my case is the headphone socket as it is a dual optical/analog 3.5mm socket. If the card is not 5.1 capable, the best that you can do is 2.1 (left and right and sub).