Dell Precision T3400 Guide De Référence Rapide page 16

IEEE 1394 connector
5
(optional)
USB 2.0 connectors
6
(2)
power button
7
16
Quick Reference Guide
Use the optional IEEE 1394 connector for high-speed
data devices such as digital video cameras and external
storage devices.
Use the front USB connectors for devices that you
connect occasionally, such as flash memory keys or
cameras, or for bootable USB devices (see "System
Setup" in your User's Guide for more information on
booting to a USB device).
NOTE:
It is recommended that you use the back USB
connectors for devices that typically remain connected,
such as printers and keyboards.
Press to turn on the computer.
NOTICE:
To avoid losing data, do not use the
power button to turn off the computer. Instead,
perform an operating system shutdown.
NOTICE:
If your operating system has ACPI
enabled, when you press the power button the
computer will perform an operating system
shutdown.
NOTE:
The power button can also be used to wake the
system or to place it into a power-saving state (see
"Power Management" in your User's Guide).