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If you can see in the lower left when

I added a 600mhz idle clock as well when on battery, by checking B/2 and adding 600mhz@.875v. Not sure if this will give me any noticeable battery boost but every little bit counts.


I also added a 600MHz vs .875v. line to the coolbook conf in my ultimate MBA 11", but I'm not sure if this is a good solution.... I felt some difficulties in scrolling the web pages in firefox and safari (not so smoothed the scrolling in "rich" webpages and with some small delays) maybe this is related with the CPU running in 600 Mhz for such "simple" tasks (I need to further investigate with other throttling levels - used medium -).... I made no definitive conclusions regarding the battery lifetime with this triple conf, but maybe some gains were obtained...however I didn't like the web scrolling bahaviour, so I returned to my dual conf 1,6 and 800 versus .875v.
 
Anyone tried any voltages lower than 0.875v (accessible via the a terminal launch of coolbook with a switch according to the manual)?
 
I am still looking for solution to run Skype on a new MBA 13". I tried it, but the noise of 4500+rpm on an MBA is beyond my comfort zone.

Would coolbook be a solution? I mean, would it significantly impact noise when using Sykpe or flash vdo?
 
I got my macbook air 11" today and have been playing with coolbook.

I've added a single setting only;

1600MHZ - 0.8750 V

To both battery and adapter.

The machine is stable, but from my experiences it has made a noticeable difference to temperature and battery life. Beforehand the battery statistics showed exactly 5 hours at 99% charge, after making the change I'm at 84% with 6 hours 13 minutes remaining.

I tested temperature whilst watching fullscreen flash 720p, and noticed that the CPU was on average 66 C after 30 minutes of watching @ 0.875V whilst with stock settings it was about 70/69 C.

Cheers.
 
hummm

I got my macbook air 11" today and have been playing with coolbook.

I've added a single setting only;

1600MHZ - 0.8750 V

To both battery and adapter.

The machine is stable, but from my experiences it has made a noticeable difference to temperature and battery life. Beforehand the battery statistics showed exactly 5 hours at 99% charge, after making the change I'm at 84% with 6 hours 13 minutes remaining.

I tested temperature whilst watching fullscreen flash 720p, and noticed that the CPU was on average 66 C after 30 minutes of watching @ 0.875V whilst with stock settings it was about 70/69 C.

Cheers.


I made several experiments with coolbook in my MBA 11". The obtained "extension" of battery lifetime is very dependent on the usage of the machine. I will say that maybe a gain of 30 min is the value for which I had converged (for normal use, e.g. wifi, web browsing, some itunes etc.). No more than that I think... but it is a significant improvement for traveling scenarios.
 
Anyone tried any voltages lower than 0.875v (accessible via the a terminal launch of coolbook with a switch according to the manual)?

I would also want to know how it's done. I'm a new mac convert and I'm not familiar with terminal commands. I have a MBA 11 ultimate and .8750v works on all frequencies. I would like to find out if I can go even lower on voltage. Does anyone know how it's done? TIA.
 
I would also want to know how it's done. I'm a new mac convert and I'm not familiar with terminal commands. I have a MBA 11 ultimate and .8750v works on all frequencies. I would like to find out if I can go even lower on voltage. Does anyone know how it's done? TIA.

It's described in the manual - basically you open coolbook from terminal (see manual) and it 'unlocks' other voltages to try.
 
It's described in the manual - basically you open coolbook from terminal (see manual) and it 'unlocks' other voltages to try.

can anyone give a more detailed guide on how this is done? thank you. i tried with no success
 
The manual says you can configure CoolBook to scan for more voltage settings (not just the default ones).

To configure it, just open your Terminal and input the following command:

defaults write se.coolbook.CoolBookController2 LoopCnt x

Where x is the number of voltage settings you want CoolBook to show (or try to scan, I couldn't figure it).

Well, I tried it with x=15 and x=25 and… nothing different appeared.

That's all I can contribute. :)
 
So on the whole people are getting around +30mins of average use?

I think it really depends on your level of CPU usage. Today for mostly web browsing and reading and whatnot I would say I probably got +1 hour of life out of my 13" MBA.
 
The manual says you can configure CoolBook to scan for more voltage settings (not just the default ones).

To configure it, just open your Terminal and input the following command:

defaults write se.coolbook.CoolBookController2 LoopCnt x

Where x is the number of voltage settings you want CoolBook to show (or try to scan, I couldn't figure it).

Well, I tried it with x=15 and x=25 and… nothing different appeared.

That's all I can contribute. :)

Same, no more voltages here. I tried 50 and 99. haha. It sucks because I'm pretty sure these CPUs can run even lower if we had the option.
 
It was proven some weeks ago in this forum that decreasing the MHz can actually decrease the battery because when the processor runs slower, it has to work for a longer time to clear the same task. As small stuff as even scrolling a web page requires a lot of cpu work, it is only when the computer is doing NOTHING where you gain from decreasing the MHz.

It's an interesting discussion I think, but the most important thing is always to set the voltage to 0,875 V.

(I run a single setting - 1400 MHz 0,875 V)

That actually does not make any sense unless there is a bug in the software that LOCKS it to the lower frequency for longer than it should. Idle speed is just that, the speed that the processor runs at when its at (or very close to) idle. Once something that actually requires some processing power happens it should ramp up right away.

Oh, and the software does appear to work rather nicely. I'm at 82% with my screen at 50% and i'm showing 7 hours left. Got a few background processes going but most are sitting idle.
 
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Just got coolbook registered.

props to magnus, definitely worth the $10

I was on the fence, but i now am glad i went for it.

you can add 600 and 700 mhz settings too on the 11". bonus!
 
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Ok let me get this straight.

Coolbook lowers the voltage of the CPU, and hence by doing so the battery life is increased; correct?

What are the effects of lowering the CPU voltage apart from battery life? Will it decrease the performance of the CPU? Will I notice anything? Or is it a win-win situation?

Thanks - I'm just slightly confused^^
 
Ok let me get this straight.

Coolbook lowers the voltage of the CPU, and hence by doing so the battery life is increased; correct?

What are the effects of lowering the CPU voltage apart from battery life? Will it decrease the performance of the CPU? Will I notice anything? Or is it a win-win situation?

Thanks - I'm just slightly confused^^

The potential drawback is an unstable system. Intel rates their CPU's to operate at a certain speed at a specified voltage. Since not all processor dye are created equal some can operate at at their rated speed with less power than others. Intel isn't going to test every single CPU core so they just set a voltage high enough that even the less perfect ones will be stable. We're simply hoping we don't have one of the crappy ones.
 
So an unstable system is a possibility.

Is there anyway the internals might be damaged or rendered less efficient?
 
So an unstable system is a possibility.

Is there anyway the internals might be damaged or rendered less efficient?
No hardware will be damaged. And by "unstable", all that can happen is that the computer will shut off. This is what happens when you run something superheavy and the voltage is not enough.

On my 11" Air, I run at the lowest voltage, I play some Starcraft 2 and it has never been shut off.
 
does coolbook come with presets or do you have to configure it yourself?
if it is configured by yourself aint that a bit dangerous?
and how do you know that the changes your making are making a difference
 
does coolbook come with presets or do you have to configure it yourself?
CoolBook comes with the presets that your computers are using. Thus, there will be change if you don't manually change the presets.
if it is configured by yourself aint that a bit dangerous?
If you read this thread, you will learn that it is not dangerous. I myself run at lowest possible voltage all the time.
and how do you know that the changes your making are making a difference
CoolBook shows the temperature of the cpu, you will be able that this drops some degrees after some time. I think you know how to detect change in battery and fan noise.
 
CoolBook comes with the presets that your computers are using. Thus, there will be change if you don't manually change the presets.

If you read this thread, you will learn that it is not dangerous. I myself run at lowest possible voltage all the time.

CoolBook shows the temperature of the cpu, you will be able that this drops some degrees after some time. I think you know how to detect change in battery and fan noise.

thanks for all your help mate, much appreciated
 
I've attached a screenshot of my settings for anyone confused.

I've run this for a week now- no problems. Battery setting is the same as adapter.
 

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