your spec considered powerful already. but maybe got lags la when in open area. my notebook spec:

1. core duo t2400
2.intel shared graphic memory
3. 1gb ram

with this spec i can play the game. but off course have lags. but this game does not much accuracy unlike some other games such as simulations or action games. so, i can accept the lags.

btw, yours have dedicated graphic card. should be more than ok.