17 R3, multiple 4K monitors through docking station

@cach22  It's Thunderbolt 3, not Thunderbird, but yes Thunderbolt 3 would allow you to run dual 4K 60 Hz displays.  You don't even need a full docking station if you only want to run displays.  You can get a Thunderbolt 3 to Dual DisplayPort adapter (or Thunderbolt 3 to Dual HDMI 2.0 adapter if you prefer), but if you want a full docking station, then there are Thunderbolt 3 docks like the Dell WD19TB.  However, you would not be able to properly charge an Alienware 17 R3 from a docking station since that system requires much more power than can be delivered over USB-C/TB3.

@takiyon  If you want to verify which GPU controls the USB-C/TB3 port, connect a display to that port (it doesn't have to be through a dock), then open NVIDIA Control Panel and go to the Surround/PhysX section.  In there you will see a diagram showing which GPU controls each display.  But even if the output is wired to the Intel GPU, that does NOT mean that you will be unable to use the NVIDIA GPU.  The NVIDIA GPU can still work through the Intel GPU using technology called NVIDIA Optimus.  If you want to understand the different types of multi-GPU laptop designs and their various benefits and drawbacks, see the post I wrote that is marked as the answer in this thread.

But even if the Intel GPU controls the display outputs, you would be able to run dual 4K 60 Hz displays through a Thunderbolt 3 dock.  Just note that if you get a WD19TB, there are some restrictions on the port combinations you can use in order to run dual 4K 60 Hz, and those restrictions are different based on whether the source system supports DisplayPort HBR2 or HBR3.  If the Intel GPU controls the outputs, it will be an HBR2 system.  If the NVIDIA GPU controls the outputs, it will probably be an HBR3 system.  So just make sure you try the correct port combinations.  Those are explained in the WD19TB User Guide on support.dell.com.