What card / motherboard are you using? There is an industry standard for colour coding (
https://en.wikipedia.org/wiki/Sound_card ) but it's better if you can refer to the actual manual to be absolutely sure. You can also check your control panel to see if you've got sound card controller software as that will often show you what the different outputs / inputs are.
The main one to be concerned with would be the mic in (pink) or audio in (light blue), but again it's best if you can either have a look at the manual or the control software.
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