You can watch the video as I step through developing the code (apologies for bad sound, I’m travelling atm!).
Full source code is available from the link in the footer of this article.
If you load up the source in VS, please note You may well need to set the linker “additional include directories” or remove the entry currently in there – there are some issues with installing the Driver Development Toolkit that clobbers some of the SDK paths.
If you’re not familiar with WMI (Windows Management Instrumentation) it provides a common interface for accessing device level and performance level data from a fairly high level. Because it’s COM, it can be accessed throughout Windows pretty agnostically without facing the barriers of only being accessable to a particular programming language or runtime.