I'm not sure if this is a problem with my exact model or if I'm just extrapolating the claimed 8 hours for a use case that's more intensive. I have the 15" with 16GB ram, 2.3ghz and the 750m. The following is while connected to wifi with full strength, playing music at half volume and screen at half brightness with 1920x1200 resolution. I'm not sure what is killing my battery life as I really don't have that much going on. I'm not running anything with videos or flash in Chrome. I just have about 20 tabs open for normal browsing. I'm thinking running at 1920x1200 might be the culprit here as it seems to always force the high perf mode.