Apologies for resurrecting an old thread, but it might help people like me who ran into the same issue...
I had the same issue with my laptop and GTX 660M. I updated to the latest nvidia drivers today and the game no longer gives that Direct X 12 error
This user has no biography set up yet.
Number of posts
Oh, That Was Fun
Has logged in and played in all legacy Gears of War games (1, 2, 3, Judgement) on this Gamertag