Asus Crosshair IV Extreme Manual page 72

4. USB connectors (10-1 pin USB78, USB910, USB1112)
These connectors are for USB 2.0 ports. Connect the USB module cables to
these connectors, then install the modules to slots opening at the back of the
system chassis. This 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!
You can connect the USB cable to ASUS Q-Connector (USB, blue) first, and
then install the Q-Connector (USB) to the USB connector onboard.
2-42 Chapter 2: Hardware information