Originally Posted by JJCG
Go to device manager and view the hardware.
That might be difficult if there's a big ol' yellow question mark next to the device and a generic name like "multimedia device" or the ever famous "Unknown Device".
If that is truly the case, then you have 2 options.
1. You can try updating device driver automatically via device manager. This may have been what was JJCG's intent, but wasn't clearly stated.
2. If updating driver via device manager fails, then you will need to open the case and look at the sound card, video card ... etc for manufacturer brands and model numbers. If everything is on board, look for the motherboard manufacturer brand and model number. Once you have these, go to the manufacturers respective websites and search for specific drivers and download.