Yeah, it bothers me that he recommended this card for Sims 4 because those specs aren't released. I don't see how he could possibly know this card will run it. Sims 4 won't be released for almost a year. So, this casts doubt on his ability to know whether this card will run Sims 3, which is the real issue. It makes me suspect he didn't really know what he was talking about and that's always a real problem in a computer store. We'd like to think they can answer these questions, but many times they can't. Further on this point, I looked up your card and compared it to the one I put in my computer earlier this year. Carl picked it out for me and it's supposed to be quite powerful. There are lots that are much more powerful, but mine is supposedly a very good video card for Sims 3. And, seriously, it will barely run the game. It doesn't act like I really wanted it to. But it gets me by for now. So, anyway, here are the specs for your card and mine.
MSI 7770:
640 Stream Processors
1GB 128-bit GDDR5
PCI Express 3.0 x16
Radeon HD 7850:
1024 Stream Processors
1GB 256-bit GDDR5
PCI Express 3.0 x16
Now, I'm far from a technical expert, but you can see where my card has higher marks (1024 Stream Processors and 256-bit). I have no idea what those things mean or how important they are, but maybe you still don't have a powerful enough card. It's a possibility I think.
As for other possibilities, you've said that you have done all of the suggestions and tricks that we can think of. You've done a complete un-install and re-install of the game? Wiped all of it from your computer and started again? If you haven't (and even if you have), I think you'll have to do it. I also suggest you do the manual un-install. You'll find the topic for that
here.I just saw what Wai said and the response. Those cleanup procedures are definitely important. Bear, how much space do you have on the drive running Sims?
My computer is set up to run Sims 3 on my C Drive and all of my other stuff is on a storage D Drive. I don't know how Sims 3 would run on a drive other than the main C Drive. It's a 300 GB drive and I'm using 163 GB, the vast majority of which is Sims 3. The game really is just a beast to run, as Seabody says. The longer it's installed and the more that's added to it, the more power it's going to need. Now that we're at the end of Sims 3 releases, most of us are having to wrangle this massive beast!
My thoughts on other things... if you're doing a clean re-install, Island Paradise shouldn't be breaking the game. However, if you've got all of your old files still in the game, that could be part of the problem. The Twinbrook file you mentioned in the other thread is massive. There's really no surprise that your game is having a hard time with that one. It's possible that it could be affecting the entire game. You might have to take a hit and wipe out all of your old games. I've had to do that more than once and I know it's not fun, but there are times when you just have to start it all from the beginning. As a very final attempt to fix this, I would remove the entire game from your computer and re-install it fresh. Add back your Store items, but nothing else. Not even the mods. If you have a freshly installed game with no mods, no CC, and no old save files and it still won't run right, you'd have to look back at the video card and/or the other specifications of the game.
I'm sorry I seem to be rambling on and on. This is a tough problem you've got and I'm trying to get all of the possibilities out there for you to look at.