Dell Precision T5400 (Late 2007) - Manual (Page 24)

24 Quick Reference Guide
7 Dell rotatable
badge To rotate the Dell badge for tower-to-desktop conversion:
remove the front panel (see "Removing the Front Panel" in your
User’s Guide), turn it over, and rotate the plastic handle behind
the badge.
8 power button,
power light Press the power button to turn on the computer. The light in the
center of this button indicates power state. For more information,
see "Power Lights" on page 27.
NOTICE: To avoid losing data, do not use the power
button to turn off the computer. Instead, perform an
operating system shutdown.
9 headphone
connector Use the headphone connector to attach headphones.
10 microphone
connector Use the microphone connector to attach a personal computer
microphone for voice or musical input into a sound or
telephony program.
11 network link light The network link light is on when a good connection exists
between a 10-Mbps, 100-Mbps, or 1000-Mbps (or 1-Gbps)
network and the computer.
12 diagnostic
lights (4) Use these lights to help you troubleshoot a computer problem
based on the diagnostic code. For more information, see "Power
Lights" on page 27.