MSISupported registry key on a PCI/PCIe device that does not support MSI RRS feed

  • Question


    Received a question from a PCI Express card vendor on the above information.

    Vendor would like to implement the above in their add-in card INF file but are concerned about what may happen if their card is plugged into a PCI Express root port that does not support MSI.

    Is it "no harm" to enable MSI via registry on a device that does not support MSI in it's PCI configuration space?

    Thursday, November 15, 2018 6:33 PM


  • If the card supports MSI at all then it is safe to enable this.   Windows can still turn it back into a regular interrupt depending on resources or hardware.

    Don Burn Windows Driver Consulting Website:

    • Marked as answer by Toby Zimmerman Friday, November 16, 2018 12:32 AM
    Thursday, November 15, 2018 8:59 PM