• PF0/PF1 Enable MSI Capability Structure : Indicates that the MSI Capability structure exists.
Note: Although it is possible to not enable MSI or MSI-X, the result would be a non-compliant core. The PCI Express Base Specification [Ref 2] requires that MSI, MSI-X, or both be enabled.
• Multiple Message Capable : Selects the number of MSI vectors to request from the Root Complex.