Well you have to make sure you meet the minimum requirements for running the game. You also need to have 20% free space on hard drive(according to the readme file). If you have any custom content or hacks you might want to consider removing them. It really sounds like a computer problem though. I have Sims2 & all expansions and stuff packs and about 3-4 GB of custom content and mine runs fine, but I have a pretty good computer.

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