Dell OptiPlex 755 - Manual (Page 182)

Removing the Computer Cover
1. Follow the procedures in Before You Begin .
2. If you have installed a padlock through the padlock ring on the back panel, remove the padlock.
3. Locate the cover release latch shown in the illustration. Then, slide the release latch back as you lift the cover.
4. Grip the sides of the computer cover and pivot the cover up using the bottom hinges as leverage points.
5. Remove the cover from the hinge tabs and set it aside on a soft nonabrasive surface.
3 network
adapter
connector
To attach your computer to a network or broadband device, connect
one end of a network cable to either a network jack or your network or
broadband device. Connect the other end of the network cable to the
network adapter connector on the back panel of your computer. A click
indicates that the network cable has been securely attached.
NOTE: Do not plug a telephone cable into the network connector.
For VPro to work, the network cable must be connected to the onboard
NIC.
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.
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.
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.
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 guard against electrical shock, always unplug your computer from the electrical outlet before removing the computer cover.
CAUTION: Graphics card heat sinks can become very hot during normal operation. Ensure that a graphics card heat sink has had sufficient time to
cool before you touch it.