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Those running Mavericks and experiencing significantly improved average battery life: what machines are you using and how old are they?

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I'm not experiencing any real change in battery life on my specced out 15" retina. Got ~5 hours before 10.9, get ~5 hours on 10.9. Makes me kind of wish I'd gone for the base CPU and saved money and battery life.

Is there a difference in battery life? The CPUs all rate the same maximum wattage (it's the same chip after all!) and CPUs are pretty good about not using power when idle.

Not to mention that a faster clocked processor has to stay active for less time to achieve the same task. A similar logic explains why LTE battery life is often better than 3G/UMTS too.

Unless I'm mistaken, isn't something like 75% of a CPU's power consumption just in pushing the clock signal around? I just assumed that a faster clock would consume more power (as a general rule).

Wikipedia seems to agree with me: http://en.wikipedia.org/wiki/CPU_power_dissipation

Yes a faster clock will do that, but as mentioned by quellhorst, you won't always be running at the fastest speed. There's also another important trick Clock Gating[1] that will reduce the power even more. That's one of the places that Intel has been working on in order to get the power usage down as much as possible to make the CPU have to dissipate less heat too. With a multi-core system it's just about absolutely necessary in order to be able to avoid overheating the die.

[1] http://en.wikipedia.org/wiki/Clock_gating

You CPU doesn't have to run at the full GHZ when it isn't in use.

Are you sure?

http://gigaom.com/2012/02/17/why-lte-sucks-your-battery-that...

May be worth running this: http://software.intel.com/en-us/articles/intel-power-gadget-... and seeing if any software you use is pegging it to maximum unnecessarily. I find that Microsoft Silverlight on MacOS tends to do that; Flash also does occasionally, though not always.

13" MacBook Pro retina.

Probably get a solid and consistent extra hour. From 6 solid hours to 7. I can push to 9 now if I lower the brightness and don't browse the web.

Same here. Really impressive.

2009, 13" MBP. Went from ~2.5 hours up to ~4hours

I'm not noticing much of an improvement on my mid-2011 MacBook Air (< 6 month old battery, 145 cycle count). The fact that the battery life indicator shows applications that are using significant amounts of energy has made me more aware of which applications are sucking away my battery life, however.

I haven't run mine on battery much since upgrading; but as you might expect I feel like my fans run less, which is much appreciated. MacBook Air 11", Mid 2012.

2013 13" MBA (with i5). I'm getting more or less the same. 7-9 hours under normal usage. Up to 10-11 under very light load.

2012 Retina MacBook Pro. An extra hour.

2012 Macbook Air 11"

Last year i7 MBA went from ~2.5h -> ~3.5-4.5h

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