TYAN S5547 Manual page 58

Storage
Controls the execution of UEFI and Legacy Storage OpROM
Do not launch / UEFI / legacy
Video
Controls the execution of UEFI and Legacy Video OpROM
Do not launch / UEFI / legacy
Other PCI devices
Determines OpRom execution policy for devices other than Network, Storage, or
Video
legacy / UEFI
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