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BIOS AND DRIVER SETTING
4.3.12 CSM Configuration
CSM Support
Enable/disable CSM support
GateA20 Active
UPON REQUEST - GA20 can be disabled using BIOS services.
ALWAYS - do not allow GA20 to be disabled; this option is useful when any RT
code is executed above 1MB.
Option ROM Messages
Set display mode for Option ROM.
INT19 Trap Response
BIOS reaction on INT19 trapping by Option ROM:
IMMEDIATE - execute the trap right away;
POSTPONED - execute the trap during legacy boot.
Boot option filter
This option controls Legacy/UEFI ROM's priority.
Network
Controls the execution of UEFI and Legacy PXE OpROM.
Storage
Controls the execution of UEFI and Legacy Storage OpROM.
Video
Allows more than two frequency ranges to be supported.
Other PCI devices
Determines OpROM execution policy for devices other than network, storage,
or video.
Figure 4 3-12: CSM Settings
