tell the exact pat number of your laptop. if you're using the AMD platform, i'd like to recommend to sell it or change the unit to some other model of dv9xxx series(intel platform). nv6150go chip is very faulty chip.
A good defrag of the HD and disk clean up maybe in order.
Also there maybe a setting in the bios where you can change the amount of ram available to you graphics card. I would also suggest looking up the games recommended or minimul specs to run the game.
If your pockets are feeling heavy you might have some luck with the Asus XG Station (external graphics card). Although I wouldn't recommend it because the price is higher than the cards actual performance.