Dell OptiPlex E1 Reference And Installation Manual page 89

Each of these switches has two positions, or settings (usually on and off ). To change
the setting of a slide switch, use a small, pointed object such as a small screwdriver or
a straightened paper clip to slide the switch to the proper position. To change the
setting of a rocker switch, use the screwdriver or paper clip to press down on the
appropriate side of the switch. In either case, do not use a pen, pencil, or other object
that might leave a residue on the switch.
DC power cable
drive in upper bay
drive interface cable
power supply
hard-disk drive
fan guard
AC power receptacle
parallel port connector
serial port 1 connector
mouse connector
keyboard connector
USB connectors
padlock ring
system board
back of computer
security cable slot
serial port 2 connector
line-in jack
video connector
expansion-card cage
line-out jack
integrated NIC connector
microphone jack
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Working Inside Your Computer 5-7