The PCI driver notifies the device driver to initialize the device. The operating system inherently relies on the IDs of devices. A change in an SID when resuming from sleep would, at a minimum, trigger a Plug and Play event. A race condition would result between the loaded driver being unloaded and the new driver being loaded, which would cause the system to hang. A new card design is defined as any design that incorporates new devices requiring any circuit board or supporting component changes.
Some events require the SID of a card to be updated.
Any component value changes on the card, including resistors and capacitors. The following are examples of SID and SVID assignments for add-on cards using different manufacturers and devices. There is one simple rule to be applied when assigning the SID and SVID for PCI devices integrated on a motherboard. It is required that all new motherboard designs have a new, unique SID assigned by the manufacturer. The operating system relies on being able to uniquely identify a device and each implementation of that device.