Advantech ASMB-925T2-00A1 User Manual page 53

3.2.2.10 CSM Configuration

CSM Support
To "Enables or disables" UEFI CSM (Compatibility Support Module) to support a
legacy PC boot process.

GateA20 Active
This items is useful when RT code is executed above 1MB. When it's set as
"Upon Request", GA20 can be disabled using BIOS services. When it's set as
"Always", it does not allow disabling GA20.
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