How to force-restart a PC with vPro technology?
vPro is a collection of technologies, and among them is the remote management you are after. To fully take advantage of vPro remote management, you need not only a vPro processor, but you also need a motherboard with the Q965 or similar chipset that has Intel's AMT (Active Management Technology) - (like this Asus board)
AMT is what allows the remote management, it is effectively a second processor on the motherboard running a management app. You talk to it, and it tells the main system what to do.
Here is the wikipedia article that explains in more depth.