Here are a few possible solutions that I've found on forums
Solution 1
While in the game, press Ctrl+Shift+C to bring up the console and enter this command: resetsim *
Make sure there is a space between resetsim and *. Press Enter.
Solution 2
1. Check if your machine comes with the K-lite Codecs. To do this, just go and look at the 'All Programs' in the Start list. If the folder's not there (named 'K-Lite Codecs' or something of the sort), you don't have them. If you do, skip the next couple steps.
2. Providing you don't have the codec pack, go here: http://www.free-codecs.com/download/...codec_pack.htm and download it. It's free and totally awesome.
3. Install it. Preferably the complete (full) version with all codecs.
4. When you're getting asked which files are to be made available for encoding/decoding by the K-lite codecs, choose all of them. Alternatively, just sellect the 'default' layout.
5. When prompted if you would like to add Windows Media Player Classic, pick Yes. You can also choose if you want any other media-playing programs to use K-Lite. I recommend you select all of them.
This should conclude your installation. Don't choose to configure the ffdshow codecs yet.
Here is where you pick up if you already have the codecs.
6. After you're done, restart your machine and then find the K-Lite folder in your Start list. There, you'll see the different codecs you installed. Two of them are called 'ffdshow video' and 'ffdshow audio' and there are the configuration tools for both. Right now, we're interested with 'ffdshow video' which is resposnible for encoding and decoding (i.e- playing) any visual media.
7. Start the configuration tool and go to 'DirectShow Control'- should be the second option on the left.
8. on the right of the screen there should be a tickbox called 'Don't use ffdshow in:' with a list of executable files. Click the Edit button and find the Sims 3 executable -TS3.exe and/or TS3W.exe.
9. If either one of them is present, delete them from the list (just erase them) and save the options by hitting Apply. Restart your machine and you should be good to go!
This should take care of the game being choppy for higher-end machines. If this doesn't help, or if you cannot find the Sims 3 executables in the ffdshow list, consider this:
10. Start the game and go to Options. See if Animation Smoothing is enabled. If not- enable it!
Always remember to check for codec updates regularly!
