The second driver is the ATI HDMI driver ( for driving the sound on the graphic card HDMI interface).
If you want a bit more info, use this; http://www.belarc.com/de/free_download.html
You can also look at your device manager,
Click on "Sound, video, and game controllers" Expand by clicking on them to get all the info about the drivers.
You can also get info on third party drivers by running
an elevated command prompt and typing: dism /online /get-drivers
( Dism is on your windows disk, if it is not on your computer)