Using laptop and external speakers simultaneously?

[darkflames]

Im trying to be able to use my laptop speakers and my external speakers at the same time. And you might be wondering why use the laptop speakers but i like hte way they sound so im trying to be able to use both the laptop and external speakers. Anyone know what i can do to do this? My laptop is the Eurocom M570u divine. Has a line in port, spdif port, and headset port. What port would i plug it in? Also anyone konw how i can get it to work? Any help would be appreciated.

Thanks