@Digitaria  I don't think you have an option with an Alienware system.  Dell does make some docks that have Power buttons explicitly meant to act as external Power buttons for the system, including power on from full shutdown and even forcibly powering off a hung system by holding it down.  The WD19 is one example.  The problem is that there's no industry-wide standard for an external Power button, so being able to use a given dock's external Power button requires firmware-level support for that dock within the system itself -- and for whatever reason, Dell hasn't implemented that support even across all of its own systems.  People who use Inspiron systems with Dell docks have the same problem.  The Latitude, Precision, and XPS systems support being controlled by the Power button found on the WD19 dock family models, but as far as I know, Alienware, Inspiron, and Vostro systems still don't.  Hopefully that changes -- and it may already have without my becoming aware of it -- but to my knowledge that's where we are today.

EDIT: The WD19 User Guide on support.dell.com as of this writing lists a single Vostro system -- the 7590 -- as "Supported", which I believe means it would support all of the dock's features, including the Power button and other "specialty" features like PXE boot, wake on LAN, and MAC Address Passthrough using the dock's Ethernet interface.  So there may be some hope of this capability trickling out to other Dell product lines.  But nothing showing for Alienware or Inspiron systems yet.

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