User Guide
1.10 Connectors
1.10.1 Rear panel connectors
1. Coaxial S/PDIF Out port. This port connects an external audio output device via an
coaxial S/PDIF cable.
2. Video Graphics Adapter (VGA) port
This 15-pin port is for a VGA monitor or other
VGA-compatible devices.
3. USB 2.0 ports 3 and 4.
These two 4-pin Universal Serial Bus (USB) ports are
available for connecting USB 2.0 devices.
4. LAN (RJ-45) port.
This port allows Gigabit connection to a Local Area Network (LAN)
through a network hub.
5. RCA Out port (right-channel). This port connects a receiver or a TV via an RCA
cable.
6. Center/Subwoofer port (orange).
This port connects the center/subwoofer speakers.
7. Rear Speaker Out port (black).
This port connects the rear speakers in a 4-channel,
6-channel, or 8-channel audio conguration.
8. Line In port (light blue).
This port connects the tape, CD, DVD player, or other audio
sources.
9. Line Out port (lime).
This port connects a headphone or a speaker. In 4-channel,
6-channel, and 8-channel conguration, the function of this port becomes Front Speaker Out.
10. Microphone port (pink).
This port connects a microphone.
11. Side Speaker Out port (gray).
This port connects the side speakers in an 8-channel
audio conguration.
Refer to the audio conguration table on next page for the function of the audio ports in 2,
4, 6, or 8-channel conguration.
LAN port LED indications
Status Left LED Right LED
OFF OFF OFF
10 Mbps connection
Orange (blinking during
data activity)
OFF
100 Mbps connection OFF
Orange (blinking during
data activity)
1 Gbps connection OFF
Green (blinking during
data activity)
Right
LED
Left
LED
LAN port
1-18 ASUS M4A78-HTPC










