Technical Product Specification

Intel® Server Board S5520UR and S5520URT TPS Connector/Header Locations and Pin-outs
Revision 1.9 Intel order number E44031-012
97
6.4.5 Power LED
The green power LED is active when the system DC power is on. The power LED is controlled
by the BIOS. The power LED reflects a combination of the state of system (DC) power and the
system ACPI state. The following table identifies the different states that can be assumed by
the power LED.
Table 49. Power LED Indicator States
State
ACPI
Power LED
Power off
No
Off
Power on
No
Solid on
S4/S5
Yes
Off
S1 Sleep
Yes
~1 Hz blink
S0
Yes
Solid on
6.4.6 System Status LED
Note: The system status LED state shows the state for the current, most severe fault. For
example, if there was a critical fault due to one source and a non-critical fault due to another
source, the system status LED state would be solid on (the state for the critical fault).
The system status LED is a bicolor LED. Green (status) is used to show a normal operation
state or a degraded operation. Amber (fault) shows the system hardware state and overrides
the green status.
The Integrated BMC-detected state and the state from other controllers, such as the
SCSI/SATA hot-swap controller state, are included in the LED state. For fault states that are
monitored by the Integrated BMC sensors, the contribution to the LED state follows the
associated sensor state, with the priority going to the most critical state that is
currently asserted.
When the server is powered down (transitions to the DC-off state or S5), the Integrated BMC is
still on standby power and retains the sensor and front panel status LED state established prior
to the power-down event.