Every time a new SP or EP is installed my graphic settings get changed. I now keep a sticky note with the info of how my settings are the way I like them. Once I install I have to go put the correct settings back, exit the game and restart. So, if you changed your settings, you have to exit and restart.
I also didn't need to have the box checked for advanced rendering turned on but now I do. I have my draw distance turned to med and high detail lots set to 1. Tree detail is med as is lighting and shadows. Reflection quality is mirrors and water (not super water). Everything else is set to high or very high. That helped keep my game up to speed and everything looking nice. Hope that helps. Good luck.