Asus P5K-E WiFi-AP User Manual page 59

10. Optical drive audio connector (4-pin CD)
This connector allows you to receive stereo audio input from sound sources
such as a CD-ROM, TV tuner, or MPEG card.
P5K-E
P5K-E Internal audio connector
11. Digital audio connector (4-1 pin SPDIF, for ASUS HDMI VGA card)
This connector is for an additional Sony/Philips Digital Interface (S/PDIF)
port(s). If you are using ASUS HDMI-equipped graphics card, connect the
HDMI card to this connector with a S/PDIF out cable.
P5K-E
P5K-E Digital audio connector
The ASUS HDMI-equipped graphics card and S/PDIF out cable are purchased
separately.
ASUS P5K-E/WiFi-AP
(black)
CD
SPDIF_OUT
2-33