I had problems with DirectX for months. Crashes/Freezing, etc... After trying literally everything, except changing hardware I think I finally found a fix. Try UNDERclocking your GPU by like 20 and if still crashes, decrease it by 20 again, reboot, try again until it stops. Try a maximum of -100.

I can't guarantee that this will work, but before that I would crash multiple times in a dungeon/boss fight, after underclocking the problem stopped completely, even in graphically intensive places like the Royal Menagerie.