Asus RS704DA-E6/PS4 - Manual (Page 58)

Chapter 4: Motherboard information 4-8
4. LAN controller setting (3-pin LAN_SW1, LAN_SW2)
These jumpers allow you to enable or disable the onboard Intel ® Intel
82574LGigabit LAN controllers. Set to pins 1–2 to activate the Gigabit LAN
feature.
5. Chassis intrusion connector (2 pin CHASSIS)
This connector is for a chassis-mounted intrusion detection sensor or switch.
Connect one end of the chassis intrusion sensor or switch cable to this
connector. The chassis intrusion sensor or switch sends a high-level signal to
this connector when a chassis component is removed or replaced. The signal
is then generated as a chassis intrusion event.
By default , the pin labeled “Chassis Signal” and “Ground” are shorted with
a jumper cap. Remove the jumper caps only when you intend to use the
chassis intrusion detection feature.