That depends on your speakers' number of channels. If it's for example, a 5.1 channel speaker then it'll be using three jacks, which is normally green, blue and black / orange. With a motherboard that only has three jacks ( pink, green and blue ), you won't be able to use a 5.1 and above channel speaker set-up.

You can however choose to connect everything on the same jack, or any available jacks if the amount of connections exceeds the amount of available audio jacks on your motherboard, but you'll end up with a speaker that won't be functioning as it was intended to.