1) Do you have ATI graphics? If not, skip to Step 3. If you don't know, right click on your desktop and see if there is an option called "Catalyst (TM) Control Center". If so, you have ATI graphics.
2) Right click on your desktop, then click "Catalyst (TM) Control Center". Click "Preferences" ("Settings"), then click "Restore to Factory Defaults".
3) Open Sims 3, click the "..." and then select "Options". Click "Restore to Defaults". Restart the game.
