I have the same problem. I've tried the steps in crinrict's post but the issue persists. On a fresh factory reset game, the first thing I did is try to open the computer menu. Its nowhere near as slow as on my 4 year old save file - but it's definitely slower than any other object's menu.
Could you post your Computer's DxDiag?
To gather a DxDiag on your computer, please follow the steps here: https://help.ea.com/en-us/help/pc/how-to-gather-dxdiag-information/
You can attach the txt file to your post directly.
DxDiag attached. My pc should definitely not be struggling to pull up a simple menu in this game :P
@crinrictUpdated (didnt realize it'd been a year, yikes lol) and restarted pc, still in the factory reset version of my game. The issue persists.
Edited to add:
I'd been playing just fine a couple days back, the issue started happening sometime after the eco living patch. Im unsure if it was there before the pack was released. I downloaded the patch yesterday but did not actually play.
