I suggest to cap your FPS to a value higher than your screen’s refresh rate.
This command will uncap your FPS when setting the value to 0, or you can cap it to let’s say 200 when using the command with a value of 200. If, in any case one of these commands worsens your performance, for example for systems running on a dual core CPU, then you can always remove the command after. These commands will make sure that the game is utilizing the most from your system’s performance, and will in turn also reduce the overall performance needed to run it on your PC. The commands you enter into this dialogue box will be applied to the game every time you launch it. In the General tab, make sure to select Set launch options. Right-click Cities Skylines and navigate to the Cities Skylines properties. In your Quality Settings, make sure to disable Shadows, set the Texture Quality to low, Level of Detail to medium, disable Anisotropic Filtering as well as Anti-Aliasing. Below, disable the Depth of field type, and the Film Grain option will not change your performance. In your Graphics preferences, set the Color Correction Override to your liking, I prefer to disable this option as well. Make sure to disable Vsync and then apply your display settings. Set your Display Mode to fullscreen, I have set it to windowed, as it’s easier to record. This will in any case reduce the visual quality, but your performance will increase in any way.
In case none of the next changes helped you as much as you wanted, then make sure to reduce the resolution option. Set the Aspect Ratio and Resolution option to your native monitor resolution. Most of these settings will depend on your system’s components, and if your CPU or GPU is a bottleneck to your performance.
Follow the instructions below In-Game Settings