Asus A55-C - Manual (Page 39)

7. USB 2.0 connectors (10-1 pin USB78, USB910)
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
480Mbps connection speed.
Never connect a 1394 cable to the USB connectors. Doing so will damage the
motherboard!
The USB 2.0 module is purchased separately.
A55-C
A55-C USB2.0 connectors
PIN 1
USB+5V
USB_P10- USB_P10+
GND
USB+5V USB_P9- USB_P9+ GND NC
USB910
PIN 1
USB+5V USB_P8- USB_P8+
GND
USB+5V USB_P7- USB_P7+ GND NC
USB78
8. Speaker connector (4-pin SPEAKER)
This 4-pin connector is for the chassis-mounted system warning speaker. The speaker
allows you to hear system beeps and warnings.
A55-C
A55-C Speaker Out Connector
+5V GND GND Speaker Out
SPEAKER
PIN 1
ASUS A55-C 1-27