DEP related if:
The Sims 3 produces exception (xcpt*.txt and xcpt*.mdmp) files in the user's My Documents directory when it crashes. To determine if the crash was caused by DEP:
1. Open an xcpt*.txt file with Notepad or your favorite text editor.
2. Scroll down to the [Exception info] section.
3. Behind address:, does it have <unknown module>? If yes, DEP caused the crash. If no, something else caused the crash.
Yes, my game would crash after a couple of seconds of game play. and I did have the <unknown module> text.