Software, not games, not operating systems, not business production programs, none of it, is going to "Overheat" a computer. It may cause the computer to work hard, but that is what the computer is supposed to do, and that is why it comes with heat sinks and cooling fans. If you choose to allow those to become clogged with lint and dust, it is you who caused the overheating.
If you ignored the System Requirements shown for a particular game and overloaded it way beyond the design parameters it was intended to handle, you are the one responsible for incrementally shortening the life of your computer over time with the overstress.
The Sims™ 3 Minimum Hardware RequirementsFOR WINDOWS XP
* 2.0 GHz P4 processor or equivalent
* 1 GB RAM
* 128 MB Video Card with support for Pixel Shader 2.0
* The latest version of DirectX 9.0c
* Microsoft Windows XP Service Pack 2
* At least 6.1 GB of hard drive space with at least 1 GB of additional space for custom content and saved games
FOR WINDOWS VISTA
* 2.4 GHz P4 processor or equivalent
* 1.5 GB RAM
* 128 MB Video Card with support for Pixel Shader 2.0
* Microsoft Windows Vista Service Pack 1
* At least 6.1 GB of hard drive space with at least 1 GB of additional space for custom content and saved games
For computers using built-in graphics chipsets under Windows, the game requires at least:
* Intel Integrated Chipset, GMA 3-Series or above
* 2.6 GHz Pentium D CPU, or 1.8 GHz Core 2 Duo, or equivalent
* 0.5 GB additional RAM
