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applestew

macrumors member
Jan 12, 2008
46
0
Pushed undervolting further form original settings...

Running
800 - 0.9
1200 - 0.9625
1400 - 0.9750
1600 - 0.9750

No KP so far. Great.... Under normal web surfing the MBA runs less than 50 degrees celsius. Under load with videos playing full screen, a tad under 62 degrees celsius.
 

applestew

macrumors member
Jan 12, 2008
46
0
Before I am loading this app, can anyone please confirm that it enables our MBAs to run youtube videos for a longer period on low fan speed around 2500rpm?
And second question: let’s suppose a task like watching flash or quicktime videos takes about 40 to 50 percent of cpu load at 1.6GHz. Will we be able to run this task on a “cooler level” when the unit is just manually set to .8 or 1.2GHz? I am still a bit afraid of doing this undervolting thing, but just lowering the cpu speed should definitely be a no risk, should it? Thanks!!

Undervolting I believe, just lowers the voltage to the chip but lets it run AT THE SAME SPECIFIED SPEED. So at the speed of say 1.6MHz, the chip runs cooler cos there is less voltage across the chip.

The second thing is throttling, the software I think checks on ur CPU load. If the load is low, it throttles down to a slower speed. This corresponds to an even lower voltage. This gives out EVEN LESS heat and consumes lesser battery. When the CPU load goes up, like watching a video, the throttling returns the CPU speed back to 1.6MHz, but applies the lower voltage. our chip runs like a normal 1.6MHx chip but runs cooler due to the lower voltage setting.
 

Thomi

macrumors member
Jan 30, 2008
51
0
Undervolting I believe, just lowers the voltage to the chip but lets it run AT THE SAME SPECIFIED SPEED. So at the speed of say 1.6MHz, the chip runs cooler cos there is less voltage across the chip.

The second thing is throttling, the software I think checks on ur CPU load. If the load is low, it throttles down to a slower speed. This corresponds to an even lower voltage. This gives out EVEN LESS heat and consumes lesser battery. When the CPU load goes up, like watching a video, the throttling returns the CPU speed back to 1.6MHz, but applies the lower voltage. our chip runs like a normal 1.6MHx chip but runs cooler due to the lower voltage setting.

All right, I am starting to understand.

1) By default our machine throttles to lower frequencies (or shut down one core) only if the heat reaches very high levels, in order to prevent thermal damage on the cpu.

2) Running CoolBook with no special settings than “throttling active” and “CoolBook active” would throttle to lower frequencies also during “easy” use like web surfing or word processing, but switch back to higher frequencies during tasks of heavy load like video editing etc. So the machine may be a bit cooler when it starts the cpu intensive task.

3) Only running CoolBook, set up with lower voltages for all frequencies of throttling will bring the final effect in cooling since the machine now will burn less energy for the cpu load at all levels of usage/speed.

4) Let’s suppose you often run tasks of medium cpu load like watching longer videos on youtube which means a cpu load of 45~50% during certain periods. Could those clips be played also with a fixed frequency of 1.2GHz or even 0.8GHz? Or would the thermal effect still be the same? Meaning they would run at 0.8GHz (and hence at lower voltage even in standard, non-tweaked set up) but then stress the cpu at 90~100% and force the fan to higher levels again? If I understood right, CoolBook would allow frequencies to be limited at lower levels (if you clear out all frequencies on the left side but the lower ones), wouldn’t it? So am curious to understand the thermal effect of throttling down with the same cpu load on a intermediate level.

Thanks again ;)
 

macsimonwoo

macrumors newbie
Feb 11, 2008
23
0
guys..i do not if it is coolbook...i have use coolbook to set the values to default again...and now i run all the youtubes videos again fullscreen...usually it would shutdown my core...now it never...but i am still monitoring these few days to see if it is isolated case...

another issue is this...i tried to multitask and push the mba and see if it will core shutdown somehow...so i run these at the same time

1. parallel running youtube video fullscreen
2. keynote presentation running fullscreen
3. firefox youtube video fullscreen
4. online radio station streaming

my activities profiler is something like this..

picture3nc9.jpg


my question is, is this temperature too high for the CPU? and if i kept running the mba at this temperature, will it fry my mba?
 

masterpace

macrumors regular
Mar 24, 2008
129
11
Montreal
Which RMClock settings?

RMClock is the windows alternative. Its mentioned in several of these posts if you bothered to read them.

Video card won't be throttled since its not the same chip as the CPU.

Indeed, I've read previous posts and installed RMClock. I've set it to "maximum performance" at 1.6 GHz and linked a lower voltage to it. I've selected the "always on" Windows energy profile as well. That doesn't seem to work at all. It seems those RMClock settings are either not applied or overrided by something: I'm still having the same heat issue and my CPU is throttling bad (it's constantly stepping down to around 700 or 800 MHz).

I would like to keep the processor at 1.6 GHz all the time until it reaches 85 C temperature, provided I undervolt it. How can I do this in RMClock?
 

dyerucf

macrumors regular
Jan 15, 2008
159
3
Alpharetta, GA
CPU Load

Question, Why do I see that it is only at 800mhz when I am running a CPU stress test?

I have a 1.8GHZ Air?

Also, I have it on .9000 for everything except .9125 for 1.8.

I am running a stress test on the cpu right now and I havnt seen it throttle up to 1.8
 

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ayeying

macrumors 601
Dec 5, 2007
4,547
13
Yay Area, CA
Remember not every chip is designed 100% exact. Some users might be able to undervolt more then others on the same exact chip.

For me, I find 0.900 Volts for all settings of 600MHz to 1.6GHz to be stable. I suspect a 1.8GHz chip would require a little higher voltage when hitting the higher clock value.
 

ayeying

macrumors 601
Dec 5, 2007
4,547
13
Yay Area, CA
Indeed, I've read previous posts and installed RMClock. I've set it to "maximum performance" at 1.6 GHz and linked a lower voltage to it. I've selected the "always on" Windows energy profile as well. That doesn't seem to work at all. It seems those RMClock settings are either not applied or overrided by something: I'm still having the same heat issue and my CPU is throttling bad (it's constantly stepping down to around 700 or 800 MHz).

I would like to keep the processor at 1.6 GHz all the time until it reaches 85 C temperature, provided I undervolt it. How can I do this in RMClock?

If your CPU is running at max, regardless of how low you undervolt it, it'll still heat up pretty rapidly. RMClock should be pretty easy to use, I've used it before but I haven't touched that program for a year now.
 

n0de

macrumors 6502
Feb 3, 2005
321
0
I have installed coolbook with the same settings as in the 1st post. I had a fullscreen quicktime .mov running, top in a terminal, an instance of Windows XP in Parallels doing a defrag and Entourage syncing in the background. I left it this way for about 20 minutes. The highest temp I saw was 71C.

What I find strange is that I rarely ever get up to 1600mhz with normal use...

I did use the "CPU Load" slider to force the CPU to 100% and have not yet hit 85C yet (~10 minutes), it hovers right around 78C.
 

dyerucf

macrumors regular
Jan 15, 2008
159
3
Alpharetta, GA
I have installed coolbook with the same settings as in the 1st post. I had a fullscreen quicktime .mov running, top in a terminal, an instance of Windows XP in Parallels doing a defrag and Entourage syncing in the background. I left it this way for about 20 minutes. The highest temp I saw was 71C.

What I find strange is that I rarely ever get up to 1600mhz with normal use...

I did use the "CPU Load" slider to force the CPU to 100% and have not yet hit 85C yet (~10 minutes), it hovers right around 78C.

When I slide the update to max the information screen never reflects anything more then 800MHZ. Also on the menu bar never changes above 800MHZ, I dont even have a 800mhz setting on battery or adapter.

Is this thing even working?
 

mattiowa

macrumors member
Jul 23, 2006
33
8
Success!!!

Following the advice of the original poster, I have also had great success in lowering the temperature and fan noise of my 1.6 MacBook Air. I've been running a number of programs simultaneously (Address Book, iCal, iTunes, Mail, Pages, Safari and Word 2004) yet the temperature has yet to exceed 58 degrees. Also, when the fan now turns on, it is hard to hear--in contrast to the jet engine noise of old.

FYI: I have both the adapter and battery settings with all the frequencies from 600 to 1,600 at .9000 volts, the throttling level at high, the temp limit at 85 degrees and throttling active.
 

thsalvo

macrumors newbie
Feb 7, 2008
12
0
Working great for me

Here are my settings:

Adapter:
1200MHz 0.9500 V
1400MHz 0.9750 V
1600MHz 0.9875 V

Battery:
800MHz 0.9000 V
1200MHz 0.9500 V

Throttling level: High
Temp Limit: 85 C

I let World of Warcraft run for 2 hours, mostly in an outdoor area, while running on AC power, and playing music in iTunes. I didn't see one core shutdown, and my CPU temperature topped out around 82 C. My CPU was switching between 1.4 GHz and 1.6 GHz. My FPS wasn't that great (8-10 fps outdoors, 20-30 fps indoors), but I had some video settings bumped up a little bit. It wasn't super-smooth, but without the core shutdowns, it's around the same level as my original MacBook 2.0 CD.

Before CoolBook, I'd get frequent core shutdowns after 20 minutes, where my FPS would drop as low as 5-6 fps outdoors, and graphic corruption would occur on some of the textures.

I'm very happy with this, and it's $10 well spent. I may try to lower my voltages for 1.4 and 1.6 GHz if everything still seems stable, and I'll post more results if so.
 

Thomi

macrumors member
Jan 30, 2008
51
0
Me to I have installed coolbook with the same settings as in the 1st post and as far as I can tell after a few first tests most tasks which were kicking the fan to max speed before are running completely silent now. :cool:
 

teek

macrumors member
Feb 12, 2008
88
0
Norway
Ok so tell my this...

If this software fixes the fan/heating issues then I wonder why
Apple didn't apply these settings and obviously they didn't but they are clearly aware of the issues so why don't they just release an update?

Also, will undervolting NOT reduce the performance on my computer or affect it in any other (negative) way ? Clearly there must be some kind of side effect when doing undervolting. So what is it?
 

mac jones

macrumors 68040
Apr 6, 2006
3,257
2
If this software fixes the fan/heating issues then I wonder why
Apple didn't apply these settings and obviously they didn't but they are clearly aware of the issues so why don't they just release an update?

Also, will undervolting NOT reduce the performance on my computer or affect it in any other (negative) way ? Clearly there must be some kind of side effect when doing undervolting. So what is it?

Very good questions (I'll pretend I know the answers)

1)It may be that Intel is the one who expects companies to use their chips 'within specs' unless instructed otherwise. In other words, Apple's hands may be tied (guessing). This is nothing new with Intel. they don't like people modifying the performance envelopes of their chips to conditions that could cause problems, however unlikely, and they have in the past taken measures to ensure you can't do this. That's why it's somewhat of a shock to see this going on with the Air.
I thought after everyone undervolted the Centrino M chip that Intel would cripple the ability to do this.

2) only time will tell what the side effects are, It does seems too good to be true. Seems like we will find some underbelly dark side to this

(I'm SUCH a pessimist):D
 

hephem

macrumors member
Jan 9, 2008
46
0
hi to all,

What a great post... Thanks to the guy who started this subject and shared his expriences with coolbook. This is the magic of Macrumors: people comming from different places all around the World linked because of an Apple product and trying to help each others.

Even if I've carefuly read the post I don't get quite well how can this be true.

1 - I mean... I've a 1.8/80... What we undervolt with Coolbook is only the CPU, right? Will the FSB or the power somehow be affected (lower)?

2 - Can you set a higher FSB with coolbook?

3 - How low can you undervolt a 1.8ghz? I mean, I know that machines have different reactions, but what would you advice at best?

4 - Would I still be able to run heavy programs such as Cut studio express?

4 - Will the performances be better? Are the better permances felt, all the way with all programs (or just in little tasks)? Are better performances felt with SSD's MBA too? If undervolting give us better performances why do some people overvolting (overclocking) instead of underclocking? :)

Thanks for your answers to my (stupid) questions!!! :D

Cheers.
 

mac jones

macrumors 68040
Apr 6, 2006
3,257
2
hi to all,

What a great post... Thanks to the guy who started this subject and shared his expriences with coolbook. This is the magic of Macrumors: people comming from different places all around the World linked because of an Apple product and trying to help each others.

Even if I've carefuly read the post I don't get quite well how can this be true.

1 - I mean... I've a 1.8/80... What we undervolt with Coolbook is only the CPU, right? Will the FSB or the power somehow be affected (lower)?

2 - How low can you undervolt a 1.8ghz? I mean, I know that machines have different reactions, but what would you advice at best?

3 - Would I still be able to run heavy programs such as Cut studio express?

4 - Will the performances be better? Are the better permances felt in all programs (or just in little tasks)? If undervolting give us better performances why do some people overvolting (overclocking) instead of underclocking? :)

Thanks for your answers to my (stupid) questions!!! :D


Cheers.

Undervolting won't give you better perfomance. And you will have to test the different settings with various apps to see what will happen.

Quite a few of us here have done this sort of thing before.

The way it's done is you reduce the voltage on the (Cpu only) in decrements, each time testing the setting by running the cpu at %100 for a while to see if the notebook is stable at this reduced voltage or if it will freeze (Yes, it could fail and you have to reboot, and hopefully it will still run. I haven't found a documented case of damage , so cross your fingers). If it doesn't freeze, you move on to the next lowest setting and repeat. You keep doing this until it does freeze (which in that case you end up using the previous higher, stable voltage setting) or you are at the bottom setting (in this case it's .9V).
I haven't read yet of a freeze (which is itself suprising as freezing can be very common with this proceedure). But the lowest 'undervolt' voltage is .9V, and I imagine if you where to go much lower you would certainly freeze it.


This is handled with Coolbook when you press test, but it only tests it for a very short period of time. You will need to run the apps you want for an extended period (hours) to really see if this is stable at the lower voltage.
 

Stratus Fear

macrumors 6502a
Jan 21, 2008
686
411
Atlanta, GA
I haven't read yet of a freeze (which is itself suprising as freezing can be very common with this proceedure). But the lowest 'undervolt' voltage is .9V, and I imagine if you where to go much lower you would certainly freeze it.

My 1.8/80 froze @ 1.6 & 1.8 w/ .9v and @ 1.8 with .9125. Next setting up for each respectively fixed that so far. I do wonder if these chips are better than Apple and Intel think. Even 1.8 @ .925v is a lot lower than the default.
 

NC MacGuy

macrumors 603
Feb 9, 2005
6,233
0
The good side of the grass.
If this software fixes the fan/heating issues then I wonder why
Apple didn't apply these settings and obviously they didn't but they are clearly aware of the issues so why don't they just release an update?

Also, will undervolting NOT reduce the performance on my computer or affect it in any other (negative) way ? Clearly there must be some kind of side effect when doing undervolting. So what is it?

Let's hope they will. There are a few issues besides heating & keyboard lighting that need to be addressed. Here's to Rev. 1 products!!

Realistically, how much real life testing could be done if they were building these just as Steve-o was introducing them? They'll get a few hundred back as returns that pass Apple tests but still are "not quite right" and figure it out.
 

dyerucf

macrumors regular
Jan 15, 2008
159
3
Alpharetta, GA
I dont see any updates

I have a 1.8GHZ air, and I dont see anything happening when I run this program. Its a registered version. I have updates to MAX and it is constantly at 800MHZ. The only thing that seems to change is the temp.

Any one have any ideas?

I have everything set to .9 except 1.8 which I bumped up slightly

Any help??
 

mac jones

macrumors 68040
Apr 6, 2006
3,257
2
My 1.8/80 froze @ 1.6 & 1.8 w/ .9v and @ 1.8 with .9125. Next setting up for each respectively fixed that so far. I do wonder if these chips are better than Apple and Intel think. Even 1.8 @ .925v is a lot lower than the default.

It's just that Intel guidelines will be zero % failure rate , hence these default voltages.

At these lower voltages that failure rate is going to increase, probably dramatically at one point. Otherwise Intel would sell these buggers as ULV chips and jack the price up a hundred bucks. ;)
 

Stratus Fear

macrumors 6502a
Jan 21, 2008
686
411
Atlanta, GA
It's just that Intel guidelines will be zero % failure rate , hence these default voltages.

At these lower voltages that failure rate is going to increase, probably dramatically at one point. Otherwise Intel would sell these buggers as ULV chips and jack the price up a hundred bucks. ;)

Oh yeah, I know that. I'm just kind of wondering how many actually fail at that rate. Success seems high in here, but then again, we're a rather small subset aren't we? :)
 
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