Webcam Diagnostics is a simple assistant which gathers many system and webcam-related information in a single place. It makes it easy to identify driver installation problems or USB issues: red circles will signal serious issues and yellow triangles will signal minor issues. Right-click a reported issue to access the context menu and click the Fix menu (if available) so that the program attempts to fix the issue or shows you a possible way to fix it.
Webcam Diagnostics can report USB issues like overcurrent or bandwidth shortage. It can also tell whether your system is correctly configured to handle a webcam (e.g. processor fast enough, recent DirectX runtime, optimal display color depth, etc.)
Download it from here.