FMA3 is supported in AMD processors starting with the Piledriver architecture and Intel starting with Haswell processorsand Broadwell processors since 2014.

Mod Edit - Fix on the way, though not up in the west yet

As the titles says, the game's implementation of Denuvo requires fma3 instructions to boot up and basically screwing a potentinal ton of users. MHW already launched on PC on China and there's ton of people reporting this problem.Source:Thanks Denuvo.