Speaker problem

I've just bought a new 5.1 speaker system for my laptop.

The 5 speakers all connect to the subwoofer.

The subwoofer has a wire that splits into 3 wires;

lime green
black
orange


My laptop only has 1 hole for these wires.

They all fit into this 1 hole, but different speakers work when different wires are in.

The manual picture shows 3 holes where these wires should go, but I don't have them.

How do I found out if my sound-card can support 5.1?
How do I solve this?

- is it possible to get a wire that converts these 3 wires into 1?
- what do I need to get all speakers to work at the same time?
- any advice?

Thanks, Baggiez