Hello everyone,

I am currently using the following game settings:

I am expected the last setting to lock my FPS to 70 for better performance. Well, this feature works just when I'm playing on FULL-HD resolution. When I'm using 4K resolution, the FPS is locked to 30 when playing, and only 15 in the menu or during highlights. As you can see in the following screenshot, the CPU, GPU and RAM resources are just fine:

Anyway, if I'm choosing "No limit on FPS", the frame rate stays up (~120) for a few minutes and then automatically locks to 60!

However, even though the frame rate is higher in this case, the game performance is very poor , especially during highlights. Again, resources are just fine and I believe it's not a hardware limitation, but a software problem. 

Is there a way in which I can lock the FPS to 60 and still keep the game playable? Do you think the resolution is the root cause the problem? Maybe the refresh rate of the screen? The HDMI cable? 

Thanks in advance!