Yup, same here. In the earlier version on lower resolution, the screen size remained the same but post update screen size is reduced and burdens the laptop a lot more. I had to make changes to my config.ini file to lower some of the graphics settings to '0' or '1' (off or low) from the default of '1' or '2'.
Just found how to run the game in full screen at lower resolution.. Goto graphics option- choose whatever resolution you like & tick borderless window mode..now it runs fine.