HP EliteBook 8540w Mobile Workstation - Manual (Page 87)

The computer takes the following actions for a critical battery level:
● If Hibernation is enabled and the computer is on or in Standby, the computer initiates Hibernation.
● If Hibernation is disabled and the computer is on or in Standby, the computer remains briefly in
Standby, and then shuts down and loses any unsaved information.
Using battery power 75