12.Digital audio connector (6-1 pin SPDIF_C) (optional)

This connector connects an SPDIF audio module that allows digital instead of analog sound output. Connect one end of the audio cable to the SPDIF_C connector on the motherboard, and the other end to an SPDIF module that you purchased separately.

SPDIF_C

SPDIF OUT

+5V

SPDIF IN

1

P4B-M

®

GND

GND

P4B-M Digital Audio Connector

SPDIF Module

Figure 2-40 Digital Audio Connector

The SPDIF audio module does not come with the motherboard package. This module is purchased separately.

13.Serial IRQ connector (2-pin SERIRQ_CON) (optional)

This connector connects the serial IRQ onboard. Some PCI cards, such as those with PCMCIA function, require this feature.

SERIRQ_CON

SERIRQ

P4B-M

GND

P4B-M SERIRQ Connector

Figure 2-41 Serial IRQ Connector

ASUS P4B-M motherboard user guide

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