Lenovo ThinkPad T540p - Manual (Page 137)

• After you change the startup sequence, ensure that you select a correct device during a copy, a save, or a
format operation. Otherwise your data might be erased or overwritten.
• If you are using the BitLocker drive encryption, do not change the startup sequence. BitLocker drive
encryption locks the computer from starting once detects the change of startup sequence.
To change the startup sequence temporarily so that the computer starts from a desired drive, do the following:
1. Restart the computer. When the ThinkPad logo is displayed, press the F12 key.
2. Select the device that you want the computer to start from.
Note: The Boot menu will be displayed if the computer cannot start from any devices or the operating
system cannot be found.
The following table lists the Startup menu items. Default values are in boldface.
Note: Some items are displayed on the menu only if the computer supports the corresponding features.
Table 6. Startup menu items
Menu item Selection Comments
Boot Select the boot device when you
press the power button to turn on the
computer.
Network Boot Select the boot device when the
computer wakes from LAN. If Wake
On LAN is enabled, a network
administrator can turn on all of the
computers in a LAN remotely by use
of network management software.
UEFI/Legacy Boot • Both
– UEFI/Legacy Boot Priority
– UEFI First
– Legacy First
• UEFI Only
• Legacy Only
CSM Support (for UEFI Only)
• Yes
• No
Select system boot capability.
• Both: Select priority of boot
options between UEFI and Legacy.
• UEFI Only: The computer will start
from the UEFI-enabled operating
system.
• Legacy Only: The computer will
boot from any operating system
other than the UEFI-enabled one.
Note: If you select UEFI Only, the
computer cannot start from the
bootable devices that do not have the
UEFI-enabled operating system.
Compatibility Support Module (CSM)
is required for starting the legacy
operating system. If you select UEFI
Only, CSM Support is selectable.
For Both or Legacy Only mode, CSM
Support is not selectable.
Chapter 8 . Advanced configuration 121