Dell OptiPlex 745 - Manual (Page 149)

Inside Your Computer
indicates that the network cable has been securely attached.
NOTE: Do not plug a telephone cable into the network connector.
On computers with a network connector card, use the connector on the
card.
It is recommended that you use Category 5 wiring and connectors for
your network. If you must use Category 3 wiring, force the network
speed to 10 Mbps to ensure reliable operation.
4 network activity
light
Flashes a yellow light when the computer is transmitting or receiving
network data. A high volume of network traffic may make this light
appear to be in a steady "on" state.
5 line-out
connector
Use the green line-out connector (available on computers with
integrated sound) to attach headphones and most speakers with
integrated amplifiers.
On computers with a sound card, use the connector on the card.
6 line-
in/microphone
connector
Use the blue and pink line-in/microphone connector (available on
computers with integrated sound) to attach a record/playback device
such as a cassette player, CD player, or VCR; or a personal computer
microphone for voice or musical input into a sound or telephony
program.
On computers with a sound card, the microphone connector is on the
card.
7 USB 2.0
connectors (6)
Use the back USB connectors for devices that typically remain
connected, such as printers and keyboards.
8 video connector Plug the cable from your VGA-compatible monitor into the blue
connector.
NOTE: If you purchased an optional graphics card, this connector will
be covered by a cap. Connect your monitor to the connector on the
graphics card. Do not remove the cap.
NOTE: If you are using a graphics card that supports dual monitors,
use the y-cable that came with your computer.
9 serial connector Connect a serial device, such as a handheld device, to the serial port.
The default designations are COM1 for serial connector 1 and COM2 for
serial connector 2.
For more information, see System Setup Options .
CAUTION: Before you begin any of the procedures in this section, follow the safety instructions in the Product Information Guide.
CAUTION: To avoid electrical shock, always unplug your computer from the electrical outlet before removing the computer cover.
NOTICE: Be careful when opening the computer cover to ensure that you do not accidentally disconnect cables from the system board.