That's a 2 year old 512MB card, yeah? In which case yeah, it will be a bit of a bottleneck. I think if you upgraded that card then you'd get a much better experience out of the game, but don't quote me on that - I'm not an expert on other components and you haven't specified anything but the card you're using (quad core is a bit vague - do you know the processor model or the amount/type of RAM you have, etc).