Fujitsu D3320 PRIMERGY BX2560 M2 Reference Manual page 67

Keep Void Boot Options
Specifies if UEFI and legacy Boot Options for devices, which are no
longer connected to the system will be removed from "Boot Option
Priority" list. If enabled the void Boot Options will be preserved in the
"Boot Option Priorities" list. This is useful to keep the boot order of the
devices, that are temporarily disconnected from the system.
The difference between the two Setup questions "Keep Void Boot
Options" and "Remove Invalid Boot Options" is the following:
The question "Keep Void Boot Options" will change only the policy of the
UEFI and legacy boot options created by the system BIOS.
The question "Remove Invalid Boot Options" will change only the policy
of the UEFI boot options created by parties outside of the BIOS (e.g.
UEFI Windows).
Disabled
Boot Options will be removed from the "Boot Option Priority" list.
Enabled
Boot Options will not be removed from "Boot Option Priority" list.
New Boot Option Policy
Configures the rule of the Boot Option Priority list positioning for new
boot options.
Default
No rule is applied which position is chosen for new boot devices.
Place First
New boot options are positioned at the beginning.
Place Last
New boot options are positioned at the end.
Boot Removable Media
Specifies if support for booting to removable devices such as USB-Stick
is available.
Disabled
Booting to removable devices is deactivated.
Enabled
Booting to removable devices is activated.
BX2560 M2
D3320 - BIOS Setup Utility
Boot menu
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