Tests Find OS X Mountain Lion May Significantly Degrade Notebook Battery Life

BatteryresultArs Technica has been doing some testing after reports emerged that some Mountain Lion early adopters were experiencing degraded battery life after upgrading to OS X 10.8. A 46-page thread with nearly 700 replies has been growing over the past several weeks on the Apple Support Forums.

Ars writer Chris Foresman, after extended testing, discovered that the battery life of his Retina MacBook Pro review unit dropped 38% from its previous 8-hours. He was unable to narrow down blame for the battery loss to any particular bit of software or system process.

Our own testing revealed similar (and significant) drops in battery runtime after installing Mountain Lion. In previous tests, we were able to regularly achieve just over 8 hours of use by relying solely on our Retina MacBook Pro's integrated Intel HD4000 GPU. Performing the same "real-world" test using the same software applications and usage pattern, we never got the Retina MacBook Pro to run for more than a few minutes past 5 hours after a full charge.

[…]

Typically, the quad-core processor wasn't taxed beyond 5 percent capacity, except for occasional 10-20 percent spikes when loading webpages, reading or writing files, or other activities. Unexpected file system or network access, or less efficient use of the GPU, could cause additional power drain without showing significant CPU use.

One poster on Apple's support forums claims a company support representative told him that "an update will be issued via the [Mac App Store] as soon as they can work a fix".

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Top Rated Comments

ouimetnick Avatar
169 months ago
Steve Jobs would never have allowed this to happen.

Enough with that crap. Mistakes happen. Look at OSX Lion. Pretty bad. Look at MobileMe, iOS 2, iPhone 3G launch, iOS 3.1 causing random rebooting, look at iPhone 4 antenna gate. List goes on. Apple is run by human beings. Humans make mistakes. Jobs wasn't perfect either.
Score: 26 Votes (Like | Disagree)
abz1981 Avatar
169 months ago
Steve Jobs would never have allowed this to happen.
I think we should all get over the 'Steve jobs would never have let this happen' comments. How do you know what Steve would have allowed or would not have allowed. Were you his personal butler or something. You need to get over it now. Tim is in charge and he is leading apple nice and well.

Opps never saw the above post either. Good point ouimetnick
Score: 21 Votes (Like | Disagree)
kniemann Avatar
169 months ago
Steve Jobs would never have allowed this to happen.
Score: 21 Votes (Like | Disagree)
Pianoblack3 Avatar
169 months ago
Uh oh! Spaghettio!
Score: 18 Votes (Like | Disagree)
east85 Avatar
169 months ago
10.8 actually INCREASED my average battery life.
Score: 17 Votes (Like | Disagree)
Apple Knowledge Navigator Avatar
169 months ago
Can't have a topic regarding OS issues without...

Steve Jobs would never have allowed this to happen.

Score: 10 Votes (Like | Disagree)