Lenovo ThinkPad L540 User Manual page 131

1. Restart the computer. When the ThinkPad logo is displayed, press F12.
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
Boot
Network Boot
UEFI/Legacy Boot
Boot Mode
Option Keys display
Value
• Both
– UEFI/Legacy Boot Priority
– UEFI First
– Legacy First
• UEFI Only
• Legacy Only
CSM Support (for UEFI Only)
• Yes
• No
• Quick
• Diagnostics
• Disabled
• Enabled
Comments
Select the boot device when you
press the power button to turn on the
computer.
Select the boot device when the system
wakes from LAN. If Wake On LAN is
enabled, the network administrator can
turn on all of the computers in a LAN
remotely by use of network management
software.
Select system boot capability.
• Both: Select priority of boot options
between UEFI and Legacy.
• UEFI Only: The system will boot from
the UEFI enabled operating system.
• Legacy Only: The system will boot
from any operating system other than
the UEFI enabled one.
Note: If you select UEFI Only, the
system cannot boot from the bootable
devices that do not have the UEFI
enabled operating system.
Compatibility Support Module (CSM) is
required for booting the legacy operating
system. If you select UEFI Only, CSM
Support is selectable. For Both or
Legacy Only mood, CSM Support is
not selectable.
Screen during the POST:
• Quick: The ThinkPad Logo screen is
displayed.
• Diagnostics: Text messages are
displayed.
Note: You also can enter Diagnostic
mode by pressing Esc during the POST.
If you select Disabled, the "To interrupt
normal startup, press Enter." message is
not displayed during the POST.
.
Chapter 8 Advanced configuration
115