November 2020
@ambshep123 Try turning lighting and tree detail down to the minimum settings. Be sure to change the settings at the Main Menu and quit to desktop before loading a save.
If that doesn't help, try playing in windowed mode. Use cmd-return (enter) to switch at the Main Menu or once a save has loaded.
If that doesn't help either, please attach your deviceconfig.log to a post. It's in Documents > Electronic Arts > The Sims 3. You'll need to manually open the folders; the file won't show up in a search. You can delete your user and computer names, about 25 lines down, but there's nothing else in that file that can identify you.