From the same Sysinternals stable as Autoruns, Process Explorer v11.21 shows a lot of information about which handles and DLL processes have opened or loaded. So with it, you can see what is taking up your CPU's time in real time as well as which process have what handles or DLL’s open.
This tool is really for system administrators and power users but if your careful, and don't delete anything, it does give you a detailed view of what's going on under the hood.
The Process Explorer display consists of two sub-windows:
The top window always shows a list of the currently active processes, including the names of their owning accounts.
The display in the bottom window depends on the mode that Process Explorer is in. If it is in handle mode you'll see all the handles that the process selected in the top window has opened. If Process Explorer is in DLL mode you'll see the DLL's and memory-mapped files that the processes have loaded.
Process Explorer also has a powerful search capability that will quickly show you which processes have particular handles opened or DLL's loaded.
The unique capabilities of Process Explorer make it useful for tracking down DLL version problems or handle leaks, and provides insight into the way Windows and applications work.
Process Explorer works on Windows 2000 SP4 Roll up 1 or above - and that includes Windows XP and Vista.