Asus A88XM-PLUS - Manual (Page 23)

ASUS A88XM-PLUS 1-13
2. Chassis intrusion connector (4-1 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 pins labeled “Intruder” are shorted with a jumper cap. Remove
the jumper caps only when you intend to use the chassis intrusion detection
feature.
A88XM-PLUS
A88XM-PLUS Chassis intrusion connector
PIN 1
+5VSB_MB Chassis Signal GND
CHASSIS