Sony PCG-NV190P - Manual (Page 139)

The power management does not respond.
Your computer's operating system may become unstable if a lower power state, such as Hibernate, is initiated and changed
before the computer completely enters the lower power state.
To restore the computer to its normal operating stability
1. Close all open applications.
2. Restart the computer by pressing Ctrl+Alt+Delete simultaneously and clicking Restart on the Windows Task
Manager dialog box.
3. If this procedure does not work, press and hold the power button for four seconds or longer to turn off the
computer.
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