Hi, When I watch movies on my laptop on battery, I get around 2 hours Laptop Asus G75vw (2011) Intel i7 3610QM Nvidia GTX 670M 24gb RAM Intel SSD 160gb + HDD 750gb Windows 7 SP1 Pro Is there an OS that performe better than others for this unique purpose? Because when I take the train I just need to play a movie, nothing else, and the longer it last, the better thanks for your attention Bye