I just ran across this tip, and thought I’d share it with you all:

Source

To show all installed devices, follow these steps:
Open a command prompt Enter the following:

SET DEVMGR_SHOW_NONPRESENT_DEVICES=1
[cd %systemroot%\system32]
[start] compmgmt.msc

Select the Device Manager node and turn on the "Show Hidden Devices" feature by clicking the appropiate entry in the View menu. The Device Manager will now list all devices that are installed on the machine.

Please note that everything in between the brackets is not necessary (as compmgmt.msc is executed regardless of launching it or not via “start” for example)