Unless your notebook is BTO (Build to Order), otherwise, I never hear notebook can change the display card... unless damage and ask for repaire... but should be same model... and also, if your notebook is build-in display card, that mean display card onboard... you have no slot to add display card. Even you have.. you must know that,the notebook case MUST need the same size output ...
Therefore, don't think you can change the notebook display card...