I have an approximately 5 year old "gaming" computer. I just bought it under recommendation though as I don't even update my drivers myself.. I hate doing stuff like that. It runs very smoothly and I can run it on Ultra. I sometimes use mods (have some saves I put in mods for specifically) but gave up CC.. not because of performance just because of update headache and changing my mind.. which would leave the townies looking terrible.
I think the problems I end up having are just game problems like speed 3 doesn't run well unless they are all sleeping. I have problems in San Myshuno but if I don't have my sims live there it doesn't have a lasting impact on my save game over all. I have had problems with a complicated older sim save with more than 150 sims .. it might have hit over 200 even but I ended up deleting it. I felt it was corrupted. It was mostly sim pausing and standing still issues and I guess stuttering kind of. I set my sim limit at 150 now but rarely even hit 80 of my own sims per save... it works well for my normal playstyle.
