Nah, not the card. When you install a sound card, you hook that shit up inside your PC. Then to use it, you install software to make it work. Right now, your card isn't working. Maybe it's cause the software isn't working. Download new software.
What sound card do you have anyway? If it's on-board sound, you'll need to look up your motherboard and shit. If it's PCI installed, just find the name of the brand and go to their site.