ADLINK cPCI-6625 - Manual (Page 62)

50 BIOS Setup Utility
older operating systems. When Enabled, the processor will
limit the maximum CPUID input value to 03h when queried,
even if the processor supports a higher CPUID input value.
When Disabled, the processor will return the actual maximum
CPUID input value of the processor when queried.
Execute Disable Bit
XD can prevent certain classes of malicious buffer overflow
attacks when combined with a supporting OS.(Windows Server
2003 SP1, Windows XP SP2, SuSE Linux 9.2 Red Hat Enter-
prise 3 Update 3.)
Intel Virtualization
Enables/disables Intel Virtualization Technology.