Toshiba Satellite C870-E - Manual (Page 112)

Panel power on/off
You can set up your computer so that power is turned off automatically
when you close the display panel, and turned on again when you open it.
Please note that this function is only available for Sleep Mode or
Hibernation Mode, not for Shut Down Mode.
If the panel power off function is enabled, and you manually shut down
Windows, do not close the display panel until the shut down process has
been completed.
System automatic Sleep/Hibernation
This feature automatically turns off the system in Sleep or Hibernation
Mode if the computer is not used for a set duration. Refer to
Special
features , in Chapter 4 for an explanation of how to set the duration.
C870/C870D/L870/L870D/L875/L875D
User's Manual 5-10