I have a white macbook that i recieved a few years back it works great and plan on using it for a few years foward. However i recently purchased two samsung 24 inch monitors to plug in. i have it hooked up with a cable spliter and all is well except that the two monitors both display the same image and i cant find a way to change that. What are my options for both screens to be different. hopefully options on the less expensive side considering i spent all my money on these monitors