HKLM\SYSTEM\CurrentControlSet\Control Registry Tree
The HKLM\SYSTEM\CurrentControlSet\Control registry tree contains information for controlling system startup and some aspects of device configuration. The following subkeys are of particular interest:
Contains information about the device setup classes on the system. There is a subkey for each class that is named using the GUID of the setup class. Each subkey contains information about a setup class, such as the class installer (if there is one), registered class upper-filter drivers, and registered class lower-filter drivers.
Each class subkey contains other subkeys known as software keys (or, driver keys) for each device instance of that class installed in the system. Each of these software keys is named by using a device instance ID, which is a base-10, four-digit ordinal value.
Contains information about the device interfaces on the system. There is a subkey for each device interface class and entries under those subkeys for each instance of an interface that is registered for the device interface class.