I have a Lenovo Y500 with an Intel Core i7-3630QM, and normally at 64% battery life it should be hovering around 1 hr 50 minutes left. Lately at 64% it's hovering around 1 hr 9 minutes left of battery life.. I'm wondering what the problem is - if I wind up replacing the battery using one that's Lenovo manufactured, would I expect to get the same or better battery life? Or is it the problem of the laptop drivers? Or something else?