if you mean the 2 connectors on the left side IIRC they are for internal speaker connection so that the card can output sound from the speaker
one connector connects to the motherboard speaker header and the other to the actual speaker, the card sits in the middle and mixes it's own output along with the speaker beeps and bops

Thanks.
And which which?
And need some init, like soundblaster cards?

No drivers needed, I think. It's like an AdLib or Rainbow Arts Soundman.
It has an YM3812 music chip (aka OPL2).

I mean, you *can* install a driver (SOUND.COM).
It's good for some games, like Spellcasting 101.

Here's a driver that may work (not tested by me).
It contains the AdLib Jukebox, which is good for testing.

http://vogonsdrivers.com/getfile.php?fileid=145&menustate=0

The pins on the left are for internal sound.
So you can attach both the PC's internal loudspeaker and PC speaker audio output on motherboard to the card.

That way, you hear both AdLib (FM) music and PC Speaker through the internal loudspeaker. Be careful with pinout, though.
Maybe you must use the correct header for loudspeaker/motherboard sound, also.

Looks like it's an OPL2 clone, is the big chip marked SC801?

envagyok wrote on 2022-11-22, 12:30:

Thanks.
And which which?
And need some init, like soundblaster cards?

If you look at the PCB layout, you can see that only the outer pins are connected.
To figure out which connector is for input and which for output without analyzing the layout, you can simply connect the speaker to one of them.
If it makes sound, it is the output.
When it comes to input polarity, look for ground connections.

Looking at the photos, lower one should be speaker output and upper one PC-speaker input, but yes, just connect speaker to one while sound plays in a game to verify the output one. Connecting PC-speaker one falsely can result in a burned cable as there's usually 5V on one side and if it goes to GND you have a decent short... (this has happened to me in past, scary 🤣).