Hey! It would be great if the devs released a short demo (the first 15 mins for example) so that everyone could test their systems and know for sure if they can run the game.

As you can see in this thread, there will probably not be a demo of Witcher 3.
http://www.gog.com/forum/general/the_witcher_3_demo

Demo is an ancient, extinct practice. It was regarded superstition and abolished by society, because it was against sales!

Modern customs and trends demand the art of preorder and season pass!