Apple PC Compatibility Card 12-inch card - Manual (Page 57)

10 Plug one of the CD audio cables that came with your PC Compatibility Card into the
Sound In connector on the computer’s logic board.
Your PC Compatibility Card came with two CD audio cables. They are
different colors to make it easier to distinguish between them, but both work
the same way.
Attach the large plug
on the end of one of the
CD audio cables to
the connector on the
computer’s main logic
board. You can use
either CD audio
cable.
43 Installing the Card in a Power Macintosh 8500 or 9500