Asus PRIME X370-A Manual page 51

Launch CSM [Enabled]
[Auto] The system automatically detects the bootable devices and the add‑on
devices.
[Enabled] For better compatibility, enable the CSM to fully support the non‑UEFI
driver add‑on devices or the Windows
[Disabled] Disable the CSM to fully support the Windows
Security Boot.
The following four items appear when you set Launch CSM to [Enabled].
Boot Device Control [UEFI and Legacy OPROM]
Allows you to select the type of devices that you want to boot up. Configuration options:
[UEFI and Legacy OPROM] [Legacy OPROM only] [UEFI only]
Boot from Network Devices [Legacy only]
Allows you to select the type of network devices that you want to launch. Configuration
options: [Ignore] [Legacy only] [UEFI driver first]
Boot from Storage Devices [Legacy Only]
Allows you to select the type of storage devices that you want to launch. Configuration
options: [Ignore] [Legacy only] [UEFI driver first]
Boot from PCI-E/PCI Expansion Devices [Legacy Only]
Allows you to select the type of PCI‑E expansion devices that you want to launch.
Configuration options: [Legacy only] [UEFI driver first]
2.8.4 Secure Boot
Allows you to configure the Windows
the system from unauthorized access and malwares during POST.
OS Type [Other OS]
Allows you to select your installed operating system.
[Windows UEFI mode]
[Other OS]
Key Management
This allows you to manage the Secure Boot keys.
Clear Secure Boot keys
This item appears only when you load the default Secure Boot keys. This item allows
you to clear all the previously applied Secure Boot keys.
Save all Secure Boot variables
This item allows you to save all the Secure Boot keys to a USB storage device.
Chapter 2: BIOS information
Secure Boot settings and manage its keys to protect
®
This item allows you to select your installed operating system.
Execute the Microsoft
option when booting on Windows
Secure Boot compliant OS.
Get the optimized function when booting on Windows
mode. Microsoft Secure Boot only supports Windows
®
mode.
UEFI mode.
®
Security Update and
®
Secure Boot check. Only select this
®
UEFI mode or other Microsoft
® ®
non‑UEFI
®
UEFI
®
2‑30