Apple makes all MacBooks with NVidia GeForce 9400M graphics chipsets, which is also the memory controller for the processor (an integrated graphics chip.) This is not new. The older MacBook Pros all had intel integrated chips as well, although they were disabled by the presence of a dedicated graphics chip.
Their higher end MacBook Pros also come with a Nvidia 9600M GT with 256MB. This is a faster graphics chip that also reduces your battery life by an hour when it is active. Since the Mac OS is utilizes a lot of graphics calculations in its normal operation, I have been a fan of faster graphics processors. As such, I have generally argued for dedicated graphics chips.
With the 9400/9600 combination, NVidia has done something interesting. They’ve made it possible to choose which chip runs your computer at any given moment. Doing so allows the user to balance between the lower power consumption of the integrated chip and the higher graphics capability of the dedicated chip.
However, for most users, I recommend not getting the 9600. The reason I recommend this is simple. I have a MacBook Pro with the 9400/9600 combination. I have never switched over to the 9600. I run video compression on the 9400. I play games on the 9400. I don’t feel like I am suffering by not using it.
Part of this is energy consumption, and the fact that I run on battery quite a bit. However, the majority of the reason I have never used the faster chip is that you actually have to log out and back in to utilize it, then log out and back in to switch back to the lower energy chip.
I was hoping that Snow Leopard would bring the ability to change graphics chips on the fly (or better yet, utilize the higher power chip for encoding only.) Alas, that has not occurred.
As I am writing this, I have 18 programs running, with files in various states of saved and not all over the place. It is a big deal for me to log out. However, if there was really a truly compelling reason to use the 9600, I would do it. A truly compelling reason would be like the difference between encoding video on a PPC Mac Mini, or a Intel Mac Mini. That transition took an H.264 encoding from 24 hours per encoding down to two hours for the same video file.
I haven’t had a compelling reason once in the year that I’ve had this MacBook Pro. Thus, once again, I have never used the 9600 in my MacBook Pro. I doubt that most users will either.