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forcelite · Mar 31, 2003, 01:40 AM

I found this on the apple forums, want to know how many have tried it.

There has been a lot of discussion on these boards about deleting a certain preference file to address the extreme heat problems a number of owners of this otherwise fine machine.
Guess what? I'm blown away. Deleting that preference file worked very well on eliminating the heat on my machine.

Heat has been eliminated by at least 70% - 80%. Still warm but certainly not uncomfortable (at least on the left palm rest) as it was before procedure. Your mileage may vary I imagine.

Anyway here is an easy step-by-step on how I did it:

1- Delete the power management preference file (com.Apple.PowerManagement.xml) located in /private/var/db/SystemConfiguration/

How? Open Terminal: type in: sudo rm /private/var/db/SystemConfiguration/com.apple.PowerManagement.xml

Here's how to do It..

a. Open Terminal (Applications>Utilities>Terminal) b. Once in Terminal select "New Command" from "File" menu c. Type in : sudo rm /private/var/db/SystemConfiguration/com.apple.PowerManagement.xml AND put a check mark in "Run Command From Inside Shell" d. Hit the "Run" button

That's it. If you look in your Trash the preference file (com.Apple.PowerManagement.xml) is there

2. Shut down your computer

3. Reset the power manager by simultaneously pressing Shift-Control-Option-Power Button on the keyboard. Do not press the fn (Function) key while using this combination of keystrokes.

4. Wait 5 seconds.

5. Press the power button to restart the computer.

6. After boot-up empty the Trash.

7. As a result of the PM reset the time may need to be reset from Date & Time Preference Panel. All other settings were fine in my case.

That's it! Good luck.

Thanks to those people who posted most of this solution. Hopefully, I pulled it all together in this post.

forcelite · Mar 31, 2003, 02:36 PM

With all you avid mac users no one has tried this?

I get mine on wed so I will see if it has heat issue and if it does I will try this. Some PB users say heat is not an issue with thiers

Forcelite

kenw · Mar 31, 2003, 02:54 PM

I'd also like to know if this works. I figure I can bend the screen back into shape to make it close correctly, and I can trim the feet to eliminate any wobble, but I'd still like to have a fix for overheating before I order a PB12. (Just on the slight chance that I get one with a problem

.)

icruise · Mar 31, 2003, 02:54 PM

*Most* of the time, heat isn't a issue with mine, although there are times that it can get rather toasty. I am personally a little wary of deleting anything in the terminal if I don't fully understand what it does, and in any case I don't really see it as a problem to begin with. Perhaps others feel the same way.

porsche993 · Mar 31, 2003, 05:58 PM

This has got to be a myth. Here are the contents of the file in question:

boxster.xxx-xxx.com 14> more /private/var/db/SystemConfiguration/com.apple.P
rManagement.xml
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple Computer//DTD PLIST 1.0//EN" "http://www.apple.
/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
<key>AC Power</key>
<dict>
<key>Automatic Restart On Power Loss</key>
<integer>1</integer>
<key>Disk Sleep Timer</key>
<integer>0</integer>
<key>Display Sleep Timer</key>
<integer>0</integer>
<key>Reduce Processor Speed</key>
<integer>0</integer>
<key>System Sleep Timer</key>
<integer>0</integer>
<key>Wake On LAN</key>
<integer>1</integer>
<key>Wake On Modem Ring</key>
<integer>1</integer>
</dict>
<key>Battery Power</key>
<dict>
<key>Automatic Restart On Power Loss</key>
<integer>1</integer>
<key>Disk Sleep Timer</key>
<integer>0</integer>
<key>Display Sleep Timer</key>
<integer>0</integer>
<key>Reduce Processor Speed</key>
<integer>0</integer>
<key>System Sleep Timer</key>
<integer>0</integer>
<key>Wake On Modem Ring</key>
<integer>1</integer>
</dict>
</dict>
</plist>

This looks like the XML file written for from the energy management GUI. Nothing really that might effect HW performance (& heat). Perhaps the gentleman who posted the hack can post his file post-hack so that we might compare ??

sean

icruise · Mar 31, 2003, 06:28 PM

I suppose that if the file was corrupted that it could theoretically add to system heat, but I think it's more placebo than anything. And it would be foolish to expect it to reduce the temp of a normal powerbook.

BTW, as I say above, the heat issue in has been made too much of in my opinion. It's nothing to put off buying a powerbook for.

Spheric Harlot · Mar 31, 2003, 06:42 PM

Is it possible that removing the preference file reverrts to reduced processor speed?

That would certainly reduce heat.

My machine does get hot occasionally, but frankly, I prefer heat to noise every day.

-s*

spapa · Mar 31, 2003, 10:55 PM

I did it this morning. It works for my 12" pbg4. It runs much cooler than ever before.

I ran 4 quicktime movies I made for my kids at the same time on cooling pad. After 15minutes, fan runs. But today I did same thing but fan does not run at all.

http://myhome.hanafos.com/~2hi0/pictures/heattest.jpg

kenw · Mar 31, 2003, 11:33 PM

Very interesting. Let us know if you notice any strange behavior resulting from the fix. Maybe someone from Apple can tell us why this works?

gwyn ap nudd · Apr 1, 2003, 12:07 AM

can you ppl xbench your PB!@" before and after the mentoned heat hack ?

http://xbench.com/

i guess this would tell about general performances slow down worry.

thanks !

spapa · 12:20 AM

Yes... it is interesting to me too. Although it seems too small difference to notice, I feel it much cooler than before.

After the fix, I have not noticed anything different than before yet. It seems working with no problem so far. The battery life remains the same even though I did not calibrate it.

The only thing I noticed is that com.apple.PowerManagement.xml file does not exhist in private/var/db/SystemConfiguration folder any more.

I just want to make sure that it does not make a lot of difference but it makes my 12" pbg4 much cooler though...

OK I ran xbench 1.0 just right now. 2months ago, the result was 77.82. Now is the following...

Results 76.01
System Info
Xbench Version 1.0
System Version 10.2.4
Physical RAM 640 MB
Model PowerBook6,1
Processor PowerPC G4 @ 867 MHz
Version 7455 (Apollo) v3.3
L1 Cache 32K (instruction), 32K (data)
L2 Cache 256K @ 534 MHz
Bus Frequency 134 MHz
Video Card GeForce4 MX
Drive Type FUJITSU MHS2040AT D
CPU Test 97.19
GCD Recursion 99.20 3.87 Mops/sec
Floating Point Basic 93.70 315.83 Mflop/sec
AltiVec Basic 104.44 5.67 Gflop/sec
Floating Point Library 92.36 4.15 Mops/sec
Thread Test 55.47
Computation 53.94 434.54 Kops/sec, 4 threads
Lock Contention 57.08 716.50 Klocks/sec, 4 threads
Memory Test 87.65
System 74.38
Allocate 101.77 34.31 Kalloc/sec
Fill 68.52 392.90 MB/sec
Copy 62.86 314.28 MB/sec
Stream 106.66
Copy 108.54 474.66 MB/sec [altivec]
Scale 110.85 483.65 MB/sec [altivec]
Add 107.38 488.58 MB/sec [altivec]
Triad 100.44 441.35 MB/sec [altivec]
Quartz Graphics Test 88.95
Line 94.86 2.41 Klines/sec [50% alpha]
Rectangle 94.69 6.66 Krects/sec [50% alpha]
Circle 104.45 2.41 Kcircles/sec [50% alpha]
Bezier 84.77 921.15 beziers/sec [50% alpha]
Text 72.78 1.19 Kchars/sec
OpenGL Graphics Test 106.58
Spinning Squares 106.58 74.58 frames/sec
User Interface Test 69.20
Elements 69.20 23.55 refresh/sec
Disk Test 57.84
Sequential 57.44
Uncached Write 52.03 22.70 MB/sec [4K blocks]
Uncached Write 50.84 20.68 MB/sec [256K blocks]
Uncached Read 94.82 14.94 MB/sec [4K blocks]
Uncached Read 49.49 21.35 MB/sec [256K blocks]
Random 58.24
Uncached Write 71.07 1.07 MB/sec [4K blocks]
Uncached Write 50.26 11.53 MB/sec [256K blocks]
Uncached Read 57.76 0.38 MB/sec [4K blocks]
Uncached Read 57.49 11.27 MB/sec [256K blocks]

As you see, there is no big difference.

7Macfreak · Apr 1, 2003, 01:38 AM

wow, more RAM makes a big difference.. i scored 70.31 with 256mb RAM.. hmmm

forcelite · Apr 1, 2003, 01:47 AM

almost everyone on the apple forum said it helped. Also this is coming from MANY people, anyway you look at it it there is not much of a performance decrease and you are saving your book from being warped. Also this performance decrease could be from the amount of apps and such you have installed. I know this matters on windows but not sure on macs. A freshly formated drive and os instal scores higher than a few month old os with tons of apps

Force

7Macfreak · Apr 1, 2003, 11:35 PM

i just tried this, and it seems to work pretty well. i'd say 50% reduction in the heat.. which is pretty good.
and it has no apparent effects on performance. before the 'hack' xbench gave a score of 70/71... and after it scored 73.

tungtied07 · Apr 1, 2003, 11:51 PM

I just tried that, we'll see tomm if it actually make the comptuer cooler!

I'll report back what happens
thanks for the suggestion, Paul T

Sarah31 · Apr 2, 2003, 12:27 AM

no difference here at all.

icruise · Apr 2, 2003, 11:14 AM

I have reservations about this "fix" because we, frankly, don't know what the heck we are doing. One would hope that Apple (who designed and built both the computer and the operating system it runs on) released the 12" powerbooks as they are for a reason.

There is, of course, a possibility that there is something wrong with the power management for the 12", in which case I would hope the fix would find its way into an official update, either to the firmware or to the OS. In any case, as I mentioned before, the heat isn't a big issue for me, so I will wait and see what happens.

forcelite · Apr 2, 2003, 02:33 PM

I can alomst guarentee that apple will have to address the heat issue. Most likly by updating the OS becuase this will be far cheaper than a hardware modification. By the way 10.2.5 is due out in a week or so and has many updates (to many to list)bluetooth, ect

It is already leaked, but I want to wait till the official release to install it. But people who have say it does improve many things

Propofol · Apr 2, 2003, 06:23 PM

I just got a 12" PB with 10.2.3 on it. Do you know if I'll have to update to 10.2.4 first, or will 10.2.5 be a cumulative update?

forcelite · Apr 2, 2003, 06:27 PM

the people who have had the most success doing this are running 10.2.4 I would not o**** on 10.2.5 having anything in it to help the 12" heat problem, never know I could be wrong

porsche993 · Apr 2, 2003, 06:39 PM

I went ahead and tried the hack, no difference in heat. I think reseting the power management may recalibrate something, but after a few hours, the heat is back.

I'm on 10.2.4.

sean

CheesePuff · Apr 2, 2003, 06:44 PM

Originally posted by porsche993:
I went ahead and tried the hack, no difference in heat. I think reseting the power management may recalibrate something, but after a few hours, the heat is back.

I'm on 10.2.4.

sean

What about the fan?