My PC has what seems to be a standard motherboard configuration, i.e. height & socket positions. There are three sockets on the motherboard, (on-board), I know are for Speaker, Microphone, and Line In. These are not labeled on my PC. I am using the standard on-board sound card.
How do you identify the 3? I put in a line feed from a cassette player, and obviously 1 didn't work, which was the speeaker output. When I connected a speaker to this socket, speakers worked. Not so easy on the other 2 sockets, as both are designed to input sound to the PC. Only thing is, with the cassette line-in, one was louder than the other, and one was clearer than the other. Which is for the microphone, and which for the line in? Thanks.
Following on from SANTOS7's answer the symbols for the other two sockets are usually a representation of sound waves radiating with an arrow running across them. If the arrow points inward then this is Line-in, if it points outward then it is Line-out/speakers.
Thank you Xania, this is what I was hoping someone would point out, because it seems to me that there is a sort of standard configuration for ATX motherboards, though I didn't know what this configuration was.