Hello,
you can leave it at "Windows" setting.
Secure boot is only completely active, when you disable CSM under the CSM tab.
The CSM (Compatibility Support Module) let you decide, if you want to enable full secure boot with only UEFI startup environment (CSM disabled), or also startup with legacy components. CSM enabled is the standard. So you dont have to change any settings.
MB: Rampage V Extreme
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