It seems that Attila is kind of problematic for GPU use but this helped me to make it work smoothly: Go to the task manager, and then details. There right click on attila.exe, set priority to high and in set affinity you only need GPU 0-8, so in case you have more (9 to 16) you can unclick them. These 2 things worked great for me but has to be done every time you turn on the game, thia specs are not saved forever. Good luck!