Intel DH55HC Computer Hardware User Manual


 
Desktop Board Features
17
Audio Subsystem
The board supports Intel High Definition Audio through a Realtek ALC888S audio codec
as well as through the HDMI interface.
The Realtek ALC888S-based audio subsystem provides the following features:
Advanced jack sense for the back panel audio connectors that enables the audio
codec to recognize the device that is connected to an audio port. The back panel
audio connectors are capable of retasking according to the user’s definition, or can
be automatically switched depending on the recognized device type.
Stereo input and output via back panel connectors
Headphone and Mic in functions for front panel audio connectors
A signal-to-noise (S/N) ratio of 90 dB
The board provides onboard audio headers and back panel connectors.
The onboard audio headers include the following:
Front panel audio (a 2 x 5 pin header that provides headphone and mic in signals
for front panel audio connectors)
S/PDIF audio header (1 x 4 pin header)
Internal mono speaker header (1 x 2 pin header)
Front panel headphone output is supported by a separate audio channel pair, allowing
multi-streaming audio configurations such as simultaneous 6-channel (5.1) surround
sound playback and stereo audio conferencing (through speakers connected to the
back panel audio connectors and a headset connected to front panel audio
connectors).
The onboard internal mono speaker header allows connection to an internal, low-
power speaker for basic system sound capability. The subsystem is capable of driving
a target speaker load of 8 at 1 W (rms) or 4 at 1.5 W (rms).
The onboard S/PDIF header allows connection to coaxial or optical adapters for digital
audio output.
The back panel audio connectors are configurable through the audio device drivers.
Audio software and drivers are available from http://downloadcenter.intel.com/
.
LAN Subsystem
The LAN subsystem includes:
Intel 82578DC Gigabit (10/100/1000 Mb/s) Ethernet LAN controller
RJ-45 LAN connector with integrated status LEDs
LAN software and drivers are available at http://downloadcenter.intel.com/
.
Two LEDs are built into the RJ-45 LAN connector located on the back panel (see
Figure 2). These LEDs indicate the status of the LAN as shown in Table 3.