> Now onto the battery issue. IMO there's not a single laptop out there that can manage battery life better than the others. They all use practically the same batteries and it's all up to you how quickly it dies (ie. brightness, etc).
That's actually not true for a number of points. There are many things that go into the battery life, and I'll list some of the most significant ones:
- Screen (that backlight takes a lot of power, and not all backlights are the same efficiency) and other components (hard drive, RAM, etc.) - all can have a range of power efficiencies
- Battery - Makes a big difference, and there are different battery designs / configurations, believe it or not
- Peripherals - USB, Bluetooth, optical drive, ports, etc. etc. etc.
- Internal circuit design and power management - In addition to the actual chips used inside and the efficiencies of various components, the power from the battery itself has to be controlled and regulated. DC power sources are far from perfect and need additional circuitry not only for charging systems but also for running the laptop at various levels of power consumption.
- Device Drivers - Even independent of operating system, good device drivers could make or break battery life. Particularly power management for the CPU, but other components like Bluetooth, Wifi, and CD drive can be power-leveled and turned on and off intelligently.
- Operating System - An efficient operating system helps of course as you mentioned, but probably isn't as important as drivers. Linux is an extremely efficient operating system yet often gets terrible battery life compared to Windows, due to poor drivers.
In short, yes, some laptops have terrible battery life for the performance. Others have incredible battery life for the performance. Ultimately the fact is I have a laptop that runs for 7+ hours when I'm browsing the web, and there are many competing models in the same performance/weight/etc. class but none of them match up.
Computers are not some magical black box with nothing but CPU/RAM/HDD... there's a lot more going on, especially in laptops (where each one has custom motherboards and circuitry from each company).