Dell Precision R5500 Owner's Manual page 101

Internal connectors
Front panel control
HDD Back Panel :
SATA
Power
Controls and Lights
Power button light:
System ID button and light blue light — flashes (front and back of chassis) when the
Drive activity light
Network link integrity
lights (front):
Network link integrity
lights (rear):
Network activity lights
Diagnostic lights:
one 28-pin connector
two 36-pin Mini-SAS connectors; six 29-
pin HDD connectors
one 14–pin connector
off — system is off or unplugged.
solid blue light — computer is operating normally.
blinking blue light — computer is in stand by.
solid amber light — the computer does not start, indicating
a problem with the system board or power supply.
blinking amber light — indicates a problem has occurred
with the system board.
button is pressed. Press the button again to turn it off.
blue light — blinking blue light indicates that the computer
is reading data from, or writing data to the hard drive.
blue light — A good connection exists between the
network and the computer.
off (no light) — The computer is not detecting a physical
connection to the network.
green light — A good connection at 10 Mbs exists between
the network and the computer
orange light — A good connection at 100 Mbs exists
between the network and the computer.
amber light — A good connection at 1000 Mbs exists
between the network and the computer.
amber light — flashes when there is network activity on
the connection.
off — computer is off or has completed POST.
amber/blinking light — see the service manual for specific
diagnostic codes.
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