I currently have the latest 15" macbook pro that includes the NVIDIA GeForce 9400M + 9600M GT with 512MB. The passed two days I've switched between the two and found that using the 9600, my fans roar constantly and I hardly noticed a difference in rendering or anything else graphically intense. It sure did a good job at making it very hot and draining my battery much faster. So what gives? Am I crazy or does anyone else experience this?