Asus M3A78 Pro - Manual (Page 48)

1-36 Chapter 1: Product introduction
7. USB connectors (10-1 pin USB56, USB78, USB910, USB1112)
These connectors are for USB 2.0 ports. Connect the USB module cable
to any of these connectors, then install the module to a slot opening at the
back of the system chassis. These USB connectors comply with USB 2.0
specification that supports up to 480 Mbps connection speed.
Never connect a 1394 cable to the USB connectors. Doing so will damage the
motherboard!
8. Optical drive audio in connector (4-pin DVD)
These connectors allow you to receive stereo audio input from sound sources
such as a DVD-ROM, TV tuner, or MPEG card.
The USB 2.0 module is purchased separately.
You can connect the front panel USB cable to the ASUS Q-Connector (USB,
blue) first, and then install the Q-Connector (USB) to the USB connector
onboard if your chassis supports front panel USB ports.