I don't know what type of pc you have, but Shade01 is correct, we need to know the specs info first. I can tell you that normally with high end desktops like HP, Dell, etc., if you have cds that came with your pc, one of them will be a drivers disk, unless you know the make and model from your pc, you can also download and install them from that respective website, as usually there's support provided.
if you have the CD of the motherboard. please install it, it contain the sound driver or
if you dont have the CD you will have to copy the sound driver from another motherboards' CD into a pen drive.I have tried it it works.
sorry for my english you can send me mesage if you dont understand something