After 90 turn I have awful slowdown of the "calculating of turn". After finishing of all activities and pushing "turn", i must wait all calculating for 1 minute or more. Only 60 turnes in hour is too long for strategic game.
"Low preferences", reinstalling of game and other my measures didn't decide problem.
Core i5 4670, 8 Gb, NVIDIA 650Ti, Win 8.1. all updates for OS and videocard are installed.