from the mobo, its ALC892, well, yer screwed. try with
openal soft, but dont expect wonders.
Download the zip, open it, in the win32 folder is the soft_oal.dll, punt it in the same folder where your executable is, run the launcher and try out the options. i'm not 100% sure which one is the actual proper one to use however, someone else will need to tell you that one.
OpenAL version is 1.1. Never heard of OpenAL Soft so I guess is the "normal" OAL.
The kind of audio hardware is a good question to ask. I cannot find any sound card in my hardware manager. I also cannot find my motherboard there. Is that usual? 
realtek alcsomethingsomethingsomething then most likely.
Which motherboard is it? Precise info on the manufacturer and model + google will tell you. or even its manual if you still have it.
You know one of the many useful bits of info that is a FSO debug log is the sound card that is being used, which is more important than whatever the manufacturer says is on the board.
So, SF-Junky, please generate and post a debug.log.
except, as the debug log shows, "Playback device: Generic Software on Lautsprecher (High Definition Audio-Gerät)"
which is about as useless as anything else in the regards of "which sound card is it"...