OS X 10.8.2 Restores Notebook Battery Life to OS X Lion Levels

Just over a month ago, Ars Technica reported that many users had noticed a significant decrease in battery life on their notebooks after upgrading from OS X Lion to OS X Mountain Lion. In its own testing, Ars Technica saw a 38% decrease in battery life following the upgrade.

The Mac Observer followed up with more extensive testing showing a similar 33% drop in battery life on a test machine following the upgrade to OS X Mountain Lion, and also finding that OS X 10.8.1 improved battery life over the original Mountain Lion release. The improvements did not, however, bring battery life back up to the levels seen under OS X Lion.

With OS X 10.8.2 now well into testing, The Mac Observer has performed its most complete set of tests yet, not only testing the effect of moving from OS X 10.8.1 to Build 12C35 of OS X 10.8.2 on battery life, but also looking at upgrades from OS X Snow Leopard to OS X Lion.

Of most immediate impact, The Mac Observer's study shows that the testing build of OS X 10.8.2 completely restores battery life to OS X Lion levels, yielding approximately 380 minutes of power under the testing protocol, compared to 260-275 minutes under OS 10.8.0 and 280-300 minutes under OS X 10.8.1.

Just as we saw in our previous tests, the upgrade to 10.8 Mountain Lion decreased battery life significantly, by about 1 hour and 45 minutes, or 30 percent. The upgrade to 10.8.1 restored about 30 minutes of battery life for our MacBook Pro, an improvement for sure, but not nearly enough to regain lost ground.

The big change came with 10.8.2, which is still undergoing developer testing. Using the latest build, 12C35, we saw a tremendous increase in battery life, to the point where running time was a few minutes longer than even that of 10.6.8.

10 8 2 battery life
In addition, the study shows that users experienced a similar but smaller effect on battery life with the introduction of OS X Lion, an issue that was not fully resolved until the release of OS X 10.7.3 over six months after the public debut of OS X Lion.

Not all notebook users have experienced significant battery life reductions under OS X Mountain Lion, and thus it is unclear exactly what the root cause of the issue is. But for those who have been suffering from the problem, it seems that OS X 10.8.2 may deliver a resolution that will restore full battery life to their machines.

Popular Stories

2007 iPhone

Apple Discontinuing This 18-Year-Old iPhone Feature

Saturday February 8, 2025 3:51 pm PST by
The end of an 18-year era is on the horizon for the iPhone. Apple reportedly plans to announce a new iPhone SE as soon as next week, and the device is expected to feature a full-screen design with Face ID, instead of a Touch ID home button. That means Apple will no longer sell any new iPhone models with a home button, for the first time since the original iPhone launched. The home button...
oppo find n5 fingers

World's Thinnest Foldable Phone Launches Next Week

Monday February 10, 2025 3:05 am PST by
Oppo has confirmed a February 20 global launch for its Find N5, which the company claims is the world's thinnest device in the foldable phone category. The phone is expected to be re-branded as the OnePlus Open 2 in the US. The Chinese vendor has been teasing the device in the last few weeks, touting its waterproofing and nearly invisible display crease, and highlighting its thinness by compa...
m2 macbook air blue

M4 MacBook Air Release Continues to Appear Imminent

Monday February 10, 2025 10:56 am PST by
There continue to be signs of a new MacBook Air with an M4 chip, indicating that we could see the machine launch in the not too distant future. A private account on X today shared the identifiers that the MacBook Air will use, and those identifiers correspond to the M4 chip. According to the source, both the 13-inch MacBook Air and the 15-inch MacBook Air will be equipped with Apple's...
iCloud General Feature Redux

iPhone Users Who Pay for iCloud Storage Receive an All-New Perk

Thursday February 6, 2025 11:21 am PST by
If you pay for iCloud storage on your iPhone, Apple has a new perk for you, at no additional cost. iCloud+ is the official name for Apple's paid iCloud storage plans, which range from 50GB for $0.99 per month to 12TB for $59.99 per month in the United States. iCloud+ plans already come with multiple perks for free, such as Hide My Email and HomeKit Secure Video, and now there is another one...
sequoia

Apple Releases macOS Sequoia 15.3.1

Monday February 10, 2025 10:11 am PST by
Apple today released macOS Sequoia 15.3.1, a minor update to the macOS Sequoia operating system that came out last September. macOS 15.3.1 comes a few weeks after the launch of macOS Sequoia 15.3. Mac users can download the ‌‌‌macOS Sequoia‌‌‌ update through the Software Update section of System Settings. Apple has also released macOS 13.7.4 and macOS 14.7.4 for those who are...
imac video apple feature

Apple to Announce New Products Next Week

Saturday February 8, 2025 10:55 am PST by
Apple has yet to release any new devices in 2025, but at least two new products are expected to be announced next week, according to rumors. Below, we outline the new Apple products that are likely to be unveiled next week. iPhone SE 4 Apple plans to announce the long-rumored iPhone SE 4 as soon as next week, according to Bloomberg's Mark Gurman. The new iPhone SE is rumored to...
apple silicon mac lineup 2024 feature purple

Apple Increases Mac Trade-In Values for a Limited Time

Sunday February 9, 2025 3:53 pm PST by
Apple today increased its estimated trade-in values for select Mac models in the United States, with the full changes outlined below. Apple says the extra trade-in credit for select Macs is available with the purchase of an eligible new Apple device through April 2. The trade-in values increased by between $10 and $50. Model New Value Old Value MacBook Pro Up to $925 ...
iOS 18

iOS 18.4 Will Include These New Features for Your iPhone

Wednesday February 5, 2025 7:15 am PST by
iOS 18.3 was released last month, so the first iOS 18.4 beta should be coming soon. iOS 18.4 is expected to be a more substantial update for the iPhone, with several new features and changes related to Apple Intelligence and beyond. Apple's website suggests that iOS 18.4 will be released in April, following beta testing. Below, we outline what to expect from the update so far. Apple...

Top Rated Comments

D.T. Avatar
162 months ago
Lost my power adapter, running on battery right now, hope this comes out in the next 2 hours and 38 minutes ...
Score: 86 Votes (Like | Disagree)
edk99 Avatar
162 months ago
Am I reading this right that a SSD has a shorter battery life then a HDD? I would of thought something with moving parts used more power then something that has no moving parts. :confused:
Score: 41 Votes (Like | Disagree)
tanousjm Avatar
162 months ago
Maybe I'm missing something here, but aren't SSDs supposed to increase battery life compared to HDDs?

And I'm not talking about the ~5 minutes differences here, from what I've read SSDs were supposed to significantly increase battery life.

Hi guys; I performed the tests for The Mac Observer. As I explained in the article, we were also confused as to why the HDD was getting better battery life than the SSD. We looked into it and discovered that our hard drive, a Western Digital Scorpio Blue, is extremely power efficient, using .59 watts at idle and 1.4 watts while active.

This is very low for a mechanical hard drive and our high performance Vertex SSD used more power: 1.3 watts idle, 2.5 watts active.

Some low speed, energy efficient HDDs have closed the gap in power consumption with SSDs, but YMMV.
Score: 25 Votes (Like | Disagree)
Xenomorph Avatar
162 months ago
But is Safari snappier?
Score: 20 Votes (Like | Disagree)
AngerDanger Avatar
162 months ago
Introducing the all new, previous battery life. Only on Mountain Lion :apple:
Score: 15 Votes (Like | Disagree)
charleswhalley Avatar
162 months ago
OS X 10.8.2 Restores Notebook Battery Life to OS X Lion Levels

Apple are you listening. Far too many products - hardware and software are being released that clearly need months more development testing. You mojo will be lost sooner rather than later if this continues.

I wonder what the iPhone 5 has wrong with it......
Score: 14 Votes (Like | Disagree)