Asus Rampage IV Formula - Manual (Page 54)

2-30 Chapter 2: Hardware information
Chapter 2
4. USB 3.0 connector (20-1 pin USB3_56)
This connector is for the additional USB 3.0 ports, and complies with the USB 3.0
specificaton that supports up to 4.8Gbps connection speed. If the USB 3.0 front panel
cable is available from your system chassis, with this USB 3.0 connector, you can have
a front panel USB 3.0 solution.
The USB 3.0 module is purchased separately.
5. Thermal sensor cable connectors (2-pin OPT_TEMP1/2/3)
These connectors are for temperature monitoring. Connect the thermal sensor cables
to these connectors and place the other ends to the devices which you want to monitor
temperature. The optional fan1/2/3 can work with the temperature sensors for a better
cooling effect.
Enable OPT FAN1/2/3 overheat protection in BIOS if you connect thermal sensor cables
to these connectors.
The thermal sensor cables are purchased separately.