Toshiba Satellite P775 - Manual (Page 28)

An error occurs and the computer does not respond to your keyboard
commands.
If you need to restart the computer, there are three ways this can be
achieved:
Click Start, point to the arrow icon ( ) and then select
Restart from the menu.
Press CTRL, ALT and DEL simultaneously (once) to display the menu
window, then select Restart from the Shut down options.
Press the power button and hold it down for five seconds. Once the
computer has turned itself off, wait between ten and fifteen seconds
before turning the power on again by pressing the power button.
Satellite P770/P775 Series
User's Manual 1-11