Jagged Image on External Display
I have a Dell U2515H running at 2560x1440 resolution which I am using an external monitor on Mac Book Pro. When I open my design files in Illustrator (CC 2017) on my Mac OS: OS X Version: 10.12, the edges of the images (photographs and icons) are not smooth. This problem is only happening on the external monitor and not when directly viewed on my Mac.
I have tried scaling it to different resolutions as well as opening different files/images but it seems to be happening with all.
I am attaching a screenshot of the same. Are there any settings which can fix this issue?

