Click Start, RIGHT CLICK My Computer, Properties, then Hardware Manager, and it should be under Sound Devices. You most likely have onboard sound though
you can also download and use [ame="http://download.cnet.com/Belarc-Advisor/3000-2094_4-10007277.html"]Belarc Advisor[/ame] if you're not sure how to check your hardware profiles. It'll tell you more than you ever wanted to know about your computer
I'm willing to bet it is onboard
That being said, it will be onboard if you bought it from a shop
Only custom built ones / ones made to order online (where you choose the parts/components) will have different soundcards
^___^