Thanks in advance for your help. My computer kept blue-screening and I brought it to a friend to check out. He concluded that my on-board video was crashing. It runs with the card he replaced it with but it's slower than it used to be when playing games (he said it was just to get me through until I bought "a real card", just something he had lying around). I bought a new card, the EN8400GS, but Sims 3 keeps giving me this message:
Unable to start game
Device 0 cannot run this title.
No supported video graphics card detected. Please check your system hardware.
Is there another step that I'm missing? I'm running Windows 7 64 bit and it installed the drivers of its own accord . . . My computer has 8 GB or RAM and an Intel I3 3.2GHz/3.2GHz processor. Thanks again.