In case you haven't already discovered this when using a phone or notebook, battery life figures reported by manufacturers are often completely wacky.
As we reported last year, the JEITA system used by many notebook manufacturers to report battery life is fine in theory (or in some cases MobileMark), but they don't exactly go out of their way to tell you that the 6 hour rating on your notebook has nothing to do with what you'll see in real life.
Now, in a stroke of honesty, AMD's Nigel Dessau has admitted that "we are not being entirely honest with users about what PC battery life they can expect to actually experience." Not only that, but hey, "Shouldn't we, as an industry, try and fix that?"
Here is Dessau's explanation of the problem:
"Typically you only get one number - and most people have no idea what that number really means in terms of how they will actually use the device: is it city or highway, talk-time or standby? More to the point: does this number represent the PC's battery life with the machine in use, or sitting idle?"
Dessau's idea is to use a combination of idle time (where the machine is left to sit idle, and timed to see how long it takes for the battery to go dead - in AMD's case, they use a MobileMark 07 to measure this), and 3DMark06.
Which is great, but at least some of the industry is already doing this. The JEITA test (depending on how you use it) involves a combination of two tests (an idle test, and a processing intensive test) which are then averaged, though obviously even that's not accurate enough based on the numbers we're seeing.
Nigel, we admire your efforts, but the real problem is getting the industry to adopt a more accurate method. AMD can talk all it likes about 3DMark, but until the notebooks manufacturers all agree on a better system, then we'll still see misleading numbers.
Sony impressed us last year when it announced it would be moving to a more accurate method of measuring battery life, but where is the rest of the industry on this?