Which version of Windows are you running there? One thing right off to try is going into the sound, video, and game controllers section of the device manager. Once in there look for any items seeing a yellow mark on them. You should see the actual name for the audio chip.
To get an expanded list of information regarding software as well as hardwares there a free tool called System Info for Windows(SIW) will give you a full breakdown on everything.
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You have to right click on the executable to create a desktop shortcut since it doesn't make any new entries in the system registry but simply scans all system information for viewing under various catagories. But it will ID the exact audio chip for you or you can right click on the yellow marked item to choose the update driver option to see if Windows will then automatically locate the correct drivers.