Celeron processors make me break out in hives. They never perform as well as they should even on office related tasks and are not meant for gaming. But I think @RainaElf could get away with the base game and some of the earlier EPs (up through LateNite or Generations maybe) even on integrated graphics as long as they keep it cooled, the game graphics options turned down, and have realistic expectations on things like load/save time and performance. I wouldn't play TS3 on that machine, and it will struggle with things, but some gameplay shouldn't be totally impossible either.
http://modthesims.info/wiki.php?title=Game_Help:Onboard_Graphics
