Dell Latitude 5420 Owner's Manual page 240

Auto On Time Allows you to set the
time at which the
computer must turn on
automatically. The
options are:
Default Setting:
Disabled
USB Wake Allows you to enable
Support USB devices to wake
the system from
Standby.
Wireless Allows you to enable or
Radio Control disable the feature that
automatically switches
from wired or wireless
networks without
depending on the
physical connection.
Default Setting:
Disabled
Disabled
Every Day
Weekdays
NOTE: This
feature is only
functional when
the AC power
adapter is
connected. If the
AC power adapter
is removed during
Standby, the
system setup will
remove power
from all of the
USB ports to
conserve battery
power.