Original Sin is using the same game engine as Dragon Commander, so it should be fine. The expectation is that many households that may want to play co-op wouldn't necessarily have 2 gaming desktops, so one person would probably be on lower end desktop or laptop, so the game will be optimized to allow it to run on as many laptops as possible (at lower graphics settings).
That said, currently the alpha isn't very optimized (though the last update improved memory utilization). I think your system should be able to play it, though.
