I know that the video games Dune II/2000 and Battle for Dune are not considered canon with the 1984 movie, despite sharing props & overall look-and-feel. The games themselves do not mention the events of the books, and the political/economic structure shown no longer exists after the events of Dune (the first book). This leads me to believe that they take place at an earlier timeframe, but a quick search failed to reveal any official word on when they take place. And the books DID reference previous wars over control of Arrakis, so it should be possible to shoehorn the plot into the timeline.
Assuming a somewhat-intact timeline, approximately how long before the first book would the games take place? Or is this semi-intact timeline even possible?