Asus P5L 1394 - Manual (Page 46)

2-26 Chapter 2: Hardware information
5. Front panel audio connector (10-1 pin AAFP)
This connector is for a chassis-mounted front panel audio I/O module
that supports HD Audio or legacy AC´97 audio standard.
4. Optical drive audio connector (4-pin CD)
This connector is for the 4-pin audio cable that connects to the audio
connector at the back of the optical drive.
We recommend that you connect a high‑definition front panel audio
module to this connector to avail of the motherboard high‑definition
audio capability.
P5L
139
4
R
P5L 1394 Internal Audio Connector
CD
(black)
Right Audio Channel
Left Audio Channel
Ground
Ground