Dell Vostro 400 Owner's Manual page 172

Connectors
Front panel USB
Front panel audio HDA
header
Processor
Memory
Power 12V
Power
Controls and Lights
Front of computer:
Power button
Power light
Drive activity light
Rear of computer:
Link integrity light (on
integrated network adapter)
Network activity light (on
integrated network adapter)
172
Appendix
two 10-pin connectors
one 10-pin connector
one 775-pin connector
four 240-pin connectors
one 4-pin connector
one 24-pin connector
push button
blue light — Blinking blue in sleep state; solid blue
for power-on state
amber light — The blinking amber indicates a
problem with the system board. A solid amber light
when the system does not boot indicates that the
system board cannot start initialization. This could be
a system board or a power supply problem (see "Power
Problems" on page 74).
blue light — A blinking blue light indicates the
computer is reading data from or writing data to the
SATA hard drive or CD/DVD.
green 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.
yellow blinking light