Lenovo 20CD0033US Menu item Selection Comments Boot, Is Disabled, UEFI/Legacy Boot Priority, Yes

Attention:

•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 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 5. Startup menu items

Menu item	Selection		Comments
Boot			Select the boot device when you
			press the power button to turn on the
			computer.
UEFI/Legacy Boot	•	Both (if OS Optimized Defaults	Select system boot capability.
		is Disabled)	• Both: The system boots by the
	•	UEFI Only (if OS Optimized
			following UEFI/Legacy Boot Priority
		Defaults is Enabled)	setting.
	•	Legacy Only	• UEFI Only: The system boots from
	UEFI/Legacy Boot Priority		the UEFI enabled operating system.
			• Legacy Only: The system boots from
	•	UEFI First	any operating system other than the
	•	Legacy First	UEFI enabled one.
	CSM Support (for UEFI Only)		Note: If you select UEFI Only, the
			system cannot boot from the bootable
	•	No
			devices that do not have the UEFI
	•	Yes	enabled operating system.
			Compatibility Support Module (CSM) is
			required for booting the legacy operating
			system. If you select UEFI Only, CSM
			Support will be selectable. For Both or
			Legacy Only mood, CSM Support will
			not be selectable.
Boot Mode	•	Quick	The Quick boot is intended to boot the
	•	Diagnostics	operating system as soon as possible
			by reducing the POST elapsed time. The
			Diagnostics boot is to be used for the
			problem determination by performing
			tests of the devices.
Option Key Display	•	Enabled	If you select Disabled, then the message
	•	Disabled	“To interrupt normal startup, press Enter”
			will not be displayed during the POST.

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