Asus P5QC - Manual (Page 57)

ASUS P5QC 2-31
7. IEEE 1394a port connector (10-1 pin IE1394_2)
This connector is for a IEEE 1394a port. Connect the IEEE 1394a module
cable to this connector, then install the module to a slot opening at the back
of the system chassis.
Never connect a USB cable to the IEEE 1394a connector. Doing so will damage
the motherboard!