PNPDeviceID值是什么意思？

Question

I am trying to find a globally unique identifier of video cards. So I using wmi to find it then I choose PNPDeviceID which seems to be what I need.

But I am not sure whether it is globally unique among lots of computers. So I want to check the value of PNPDeviceID.

The wmic command used is:

wmic path win32_videocontroller get PNPDeviceID

The PNPDeviceID is like:

PCI\\VEN_10DE&DEV_1245&SUBSYS_00007377&REV_A1\\4&1DDDA1E7&0&0008

I guess Ven_10DE is vender id, dev_1245 is device id, subsys_00007377 is a subsystem id, rev_a1 is revision id.

But what subsystem means? What is the meaning of "4&1DDDA1E7&0&0008" and "PCI"?

Thank you!

Answer 1

PCI is a bus identifier. It refers to the PCI family of buses, which currently means PCI express (PCIe). You also might see USB here. (Not very common for video, but possible).

The other bits are just internal parameters to Windows, and have no guaranteed meaning. Generally, you expect a few bits here which would allow Windows to figure out it's a video card, and how that card is connected to the system (This tends to be more important for USB; USB hubs can form complex trees with 5 levels and 127 devices).

Given that, it's fairly obvious there are not nearly enough bits in there to have a globally unique ID. Also: in the Microsoft world, a globally unique ID is a GUID, and recognizable as such.