Inspiron 620 Sound Card options?

My Inspiron 620 has lost sound suddenly, and the sound card does not appear in device manager. All efforts to trooubleshoot/reinstall the Conextant (?) driver fail indicating a dead sound card. 

My question is can I install a sound card and is there any type/brand/model that can be recommended to install into this desktop? I am presuming that there is a pci slot for it.

Thank you for any advice.