Windows 8 Secret world = difficult to run.
I am not sure if its because of the windows 8 new "Metro" that only runs in a minimum resolution, but I have to run it in atleast 1080P. The game becomes laggy, and requires much more of my Dell xps.
Nevertheless, I run the game fine in 1080P settings, but still have yet to come across many games of which are win8 compatible.
Hence, wait a little before using win8 for a gaming reason!