Dell Precision T7400 (Late 2007) - Manual (Page 201)

Adding and Replacing Parts 201
15 Ensure that all connectors are properly cabled and firmly seated.
NOTICE: To connect a network cable, first plug the cable into the network device
and then plug the cable into the computer.
16 Replace the computer cover (see "Replacing the Computer Cover" on
page 145), reconnect the computer and devices to electrical outlets, and
then turn them on.
17 If you installed a sound card:
a Enter system setup, select Integrated Audio, and then change the
setting to Off.
b Connect external audio devices to the sound card’s connectors. Do
not connect external audio devices to the microphone,
speaker/headphone, or line-in connectors on the back panel.
1 card retention device 2 tab
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