Dell PRECISION 530 - Manual (Page 25)

About Your Computer 25
• When connecting a USB mouse or keyboard, ensure that you connect
to one of the Port 1 USB connectors on the back of the computer .
• Always attach external devices while your computer is turned off. Then
turn on the computer before turning on any external devices, unless
the documentation for the device specifies otherwise.
NOTICE: Before disconnecting a device from the computer, wait 10 to 20
seconds after turning off the computer to avoid possible damage to the system
board.
Speaker/Headphone Jack
Used to connect computer speakers, headphones, or other audio output
devices. This jack is amplified to support headphones.
IEEE 1394 (FireWire) Connector
Used to attach high-speed serial multimedia devices. For more information,
see "
IEEE 1394 (FireWire) ."
USB Connectors
Used to attach USB-compliant devices such as printers and speakers to your
computer.
NOTE: When connecting a USB mouse or keyboard, ensure that you connect
to one of the Port 1 USB connectors on the back of the computer .
NOTICE: USB devices do not operate with Microsoft Windows NT.