Re: Pismo status

Re: Pismo status

[Claudio Nieder]

Hi,

> Yeah.  The powerbook case cools both through heat rising through gaps in
> the keyboard and through the entire thing being basically one huge heat

Which made me buy an external keyboard for stationary operation, as this
heat disturbs me quite a lot. I wonder why they don't move some of the
heat producers into the screen part of the laptop, e.g. CPU graphic chip and
memory. That would remove some heat from the part which I usualy touch,
be it the keyboard, or the bottom, when I don't have a table, and put
the PowerBook directly on my legs.

                                claudio
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mailto:private@claudio.ch http://www.claudio.ch phone:+41 79 357 6743

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Pismo status

[Chris Leishman]

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Hi all,

Just curious what is/isn't current working in the latest kernels that
Ben has made available?  In particular, is power management working?? 
(I can't seem to get APM going, and it is sure draining power...)

Also - does anyone know how well the airport cards work (and who is working on
support for them?)

Thanks!

Chris Leishman

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Re: Pismo status

[Michel Dänzer]

Chris Leishman wrote:

> Just curious what is/isn't current working in the latest kernels that
> Ben has made available?

I've installed Debian on my Pismo yesterday, and the kernel provided by the
potato boot-floppies (2.2.15pre20, don't know if it's from Ben) has been
working fine so far, only thing is sound doesn't work for me (I should be able
to hear something after tuning up volume with gmix, right?).


> In particular, is power management working?? (I can't seem to get APM going,
> and it is sure draining power...)

I also wondered, my machine was getting very warm, almost hot. But then it
didn't even kick on the fan...


Michel


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______________________________________________________________________________
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Debian GNU/Linux (powerpc,i386) user \   member of XFree86, Team *AMIGA*, AUGS

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Re: Pismo status

[Sven LUTHER]

On Tue, May 16, 2000 at 10:46:43AM +0200, Michel Dänzer wrote:
> Chris Leishman wrote:
>
> > Just curious what is/isn't current working in the latest kernels that
> > Ben has made available?
>
> I've installed Debian on my Pismo yesterday, and the kernel provided by the
> potato boot-floppies (2.2.15pre20, don't know if it's from Ben) has been
> working fine so far, only thing is sound doesn't work for me (I should be able
> to hear something after tuning up volume with gmix, right?).
>
>
> > In particular, is power management working?? (I can't seem to get APM going,
> > and it is sure draining power...)
>
> I also wondered, my machine was getting very warm, almost hot. But then it
> didn't even kick on the fan...

Isn't it supposed to have no fan ?

Friendly,

Svne LUTHER

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Re: Pismo status

[Chris Leishman]

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On Tue, May 16, 2000 at 04:15:45PM +0200, Sven LUTHER wrote:
<snip>
> 
> Isn't it supposed to have no fan ?
> 

It has a little one to vent air out from on top of the heatsinks when it
gets too warm (though I don't notice it come on very often under OS 9).

Chris

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Re: Pismo status

[Tim Wojtulewicz]

>Isn't it supposed to have no fan ?
>
>

No it's definitely supposed to have a fan.  It comes on in MacOS.
The problem is that the PMU is not fully supported yet, so it doesn't
understand that the processor is too hot.  I'm trying to find
information about it, but I'm not having much luck.  If anything, try
running Paul's pmud (you can get it from rpmfind.net).  It helps a
little.

Tim

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Re: Pismo status

[Albrecht Dre_]

Tim Wojtulewicz wrote:
> No it's definitely supposed to have a fan.  It comes on in MacOS.
> The problem is that the PMU is not fully supported yet, so it doesn't
> understand that the processor is too hot.  I'm trying to find
                      ^^^^^^^^^^^^^^^^^^^^
Does this mean that I can damage the machine if I just run a high-load
program?!?


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Re: Pismo status

[Michael Schmitz]

> Tim Wojtulewicz wrote:
> > No it's definitely supposed to have a fan.  It comes on in MacOS.
> > The problem is that the PMU is not fully supported yet, so it doesn't
> > understand that the processor is too hot.  I'm trying to find
>                       ^^^^^^^^^^^^^^^^^^^^
> Does this mean that I can damage the machine if I just run a high-load
> program?!?

I strongly doubt that. The PMU should handle this autonomously, regardless
of Linux support for the PMU.

	Michael


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Re: Pismo status

[Sven LUTHER]

On Wed, May 17, 2000 at 12:54:22PM +0200, Michael Schmitz wrote:
> > Tim Wojtulewicz wrote:
> > > No it's definitely supposed to have a fan.  It comes on in MacOS.
> > > The problem is that the PMU is not fully supported yet, so it doesn't
> > > understand that the processor is too hot.  I'm trying to find
> >                       ^^^^^^^^^^^^^^^^^^^^
> > Does this mean that I can damage the machine if I just run a high-load
> > program?!?
>
> I strongly doubt that. The PMU should handle this autonomously, regardless
> of Linux support for the PMU.

Also, i think the ppc cpu will halt itself when becoming too hot, and not let
itself burn. At elast it was so since the earlier 680x0 cpus.

Friendly,

Sven LUTHER

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Re: Pismo status

[Timothy A. Seufert]

At 2:08 PM +0200 5/17/00, Sven LUTHER wrote:
>On Wed, May 17, 2000 at 12:54:22PM +0200, Michael Schmitz wrote:
>>  > Tim Wojtulewicz wrote:
>>  > > No it's definitely supposed to have a fan.  It comes on in MacOS.
>>  > > The problem is that the PMU is not fully supported yet, so it doesn't
>>  > > understand that the processor is too hot.  I'm trying to find
>>  >                       ^^^^^^^^^^^^^^^^^^^^
>>  > Does this mean that I can damage the machine if I just run a high-load
>>  > program?!?
>>
>>  I strongly doubt that. The PMU should handle this autonomously, regardless
>>  of Linux support for the PMU.
>
>Also, i think the ppc cpu will halt itself when becoming too hot,

No, it will not.

The PowerPC 750 (G3) and 7400 (G4) can both fire off an interrupt
when the on-die temperature sensor reading rises above a trigger
value (or falls below a second trigger value).  This feature *could*
be used by an operating system to slow down the CPU (through the
instruction cache throttling feature) or halt it to prevent
overheating.  However, there is no hardware feature which can halt
the CPU without software control.

>  and not let
>itself burn. At elast it was so since the earlier 680x0 cpus.

As far as I know none of the 680x0 CPUs even had an on-die
temperature sensor, let alone a thermal shutdown feature.



I just talked with somebody who worked on the 101 project (popularly
and incorrectly known as "Lombard").  At least for that machine, the
fan is controlled as follows:

The normal mode is that MacOS controls the fan through the PMU.  The
PMU is connected to a thermistor located somewhere on the
motherboard.  MacOS scans the value of this thermistor every so often
and uses the fan to cool the machine if it's getting warm.  MacOS
takes advantage of the speed control feature of the fan, so it won't
crank the fan up to full speed if it doesn't have to.

If MacOS fails to turn the fan on for some reason, the PMU acts as a
backup controller -- it is also monitoring the thermistor and will
force the fan to turn on at full speed if a moderately high (but not
yet unsafe) temperature is reached.

If the PMU's fan override fails to stop the computer's temperature
from rising, and the temperature begins to approach dangerous levels,
the PMU will simply shut the machine down without asking.  (Most Macs
since the Mac II have had a thermal shutdown feature like this,
including the desktops.)

So, at least for 101, the fan should still come on without operating
system support, followed by an abrupt shutdown if the computer gets
way too hot.


The current PowerBook G3, 102 (the one with FireWire, popularly and
in this case correctly known as "Pismo"), does have a different PMU
than 101.  Apple did a major upgrade to the PMU used with all Core99
chipset machines, 102 included.  But it's fairly unlikely that Apple
changed the fan control technique very much.

   Tim Seufert

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Re: Pismo status

[Sergio Brandano]

 There is one standard feature of automobiles that has not yet been
 implemented for computers, namely if you switch off the computer the
 cooling system should stay on until needed.

 (On my 101, I often hear the fan going on just when I need to shut
 down. The fact is that when I want to shut down, I do not want to
 wait for the fan, and I also put the screen down...)

 Sergio

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Re: Pismo status

[Sven LUTHER]

On Thu, May 18, 2000 at 09:13:37AM +0000, Sergio Brandano wrote:
>
>  There is one standard feature of automobiles that has not yet been
>  implemented for computers, namely if you switch off the computer the
>  cooling system should stay on until needed.
>
>  (On my 101, I often hear the fan going on just when I need to shut
>  down. The fact is that when I want to shut down, I do not want to
>  wait for the fan, and I also put the screen down...)

Or not power off before they finished writing to the disk or other such task
to be in a stable state, try removving the power cable from a not mobile
computer ...

Freindly,

Sven LUTHER

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Re: Pismo status

[Sergio Brandano]

>  (On my 101, I often hear the fan going on just when I need to shut
>  down. The fact is that when I want to shut down, I do not want to
>  wait for the fan, and I also put the screen down...)

>Or not power off before they finished writing to the disk or other such task
>to be in a stable state, try removving the power cable from a not mobile
>computer ...

 ... ``shutdown'' and ``unplug'' are not synonyms in my dictionary.

 SB

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Re: Pismo status

[Sven LUTHER]

On Thu, May 18, 2000 at 03:33:39PM +0000, Sergio Brandano wrote:
>
> >  (On my 101, I often hear the fan going on just when I need to shut
> >  down. The fact is that when I want to shut down, I do not want to
> >  wait for the fan, and I also put the screen down...)
>
> >Or not power off before they finished writing to the disk or other such task
> >to be in a stable state, try removving the power cable from a not mobile
> >computer ...
>
>  ... ``shutdown'' and ``unplug'' are not synonyms in my dictionary.

Well, yes, but unplugging could be much more damaging, and i guess a not
running cpu will surely not suffer from heat, ... :)))

Friendly,

Sven LUTHER

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Re: Pismo status

[Sergio Brandano]

 Sorry, I do not see your point.

 My point is that if the CPU is piping hot, and you shutdown the
 computer, no cooling is provided. This is wrong, as the fan has
 nothing to do with the OS and it *must* spin until the temperature
 reaches a safe level.

 Friendly,

 Sergio

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Re: Pismo status

[Sergio Brandano]

>>  Sorry, I do not see your point.
>>
>>  My point is that if the CPU is piping hot, and you shutdown the
>>  computer, no cooling is provided. This is wrong, as the fan has
>>  nothing to do with the OS and it *must* spin until the temperature
>>  reaches a safe level.

>Well, the fan is there to remove the exess heat generated by a running CPU, if
>you shut off the CPU, there will be no more exess heat generated, and the
>existing heat will most assuredly be dissipated to less active cooling
>mechanism. Since you cannot damage the CPU, or other pieces of the hardware,
>this should cause no problem. And i think the G3 processor is not so hot
>running, that it will be so much above the safe temperature state.

 Ok Sven. You are convinced about your idea, but I am still skeptical.
 In order to persuade me, I need a proof. Please perform this simple
 experiment, then report the result. The experiment is as follows.
 Have a nice and long trip with your car, then come back home, and
 switch the engine off ensuring that the cooling fan is not spinning.
 Let us know if your car starts again the next day.

 If you prefer, you can perform the similar experiment with your brand new
 PowerBook 500Mhz. Just run an intensive floating point application
 for a long time, then shutdown. Keep doing it every day, for a week
 or so. Let us know it your jewel works fine at the end of it.

 Friendly,

 Sergio

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Re: Pismo status

[Worth]

On Fri, 19 May 2000, Sergio Brandano wrote:

>
> >>  Sorry, I do not see your point.
> >>
> >>  My point is that if the CPU is piping hot, and you shutdown the
> >>  computer, no cooling is provided. This is wrong, as the fan has
> >>  nothing to do with the OS and it *must* spin until the temperature
> >>  reaches a safe level.
>
> >Well, the fan is there to remove the exess heat generated by a running CPU, if
> >you shut off the CPU, there will be no more exess heat generated, and the
> >existing heat will most assuredly be dissipated to less active cooling
> >mechanism. Since you cannot damage the CPU, or other pieces of the hardware,
> >this should cause no problem. And i think the G3 processor is not so hot
> >running, that it will be so much above the safe temperature state.
>
>  Ok Sven. You are convinced about your idea, but I am still skeptical.
>  In order to persuade me, I need a proof. Please perform this simple
>  experiment, then report the result. The experiment is as follows.
>  Have a nice and long trip with your car, then come back home, and
>  switch the engine off ensuring that the cooling fan is not spinning.
>  Let us know if your car starts again the next day.

Bad analogy, many cars have fans that don't run after shutdown and
they run fine every day (I've never owned own that was any other
way). The ones that run electric fans after shutdown tend to be highly
stressed small engines with thin-wall blocks in cramped engine
compartments with poor air flow and small capacity high-pressure cooling
systems. In such situations there is a potential for localized boiling of
stagnant coolant around hot spots in the block. This can result in
problems like accelerated corrosion, coolant overflow, and coolant vapor
lock. Running the fans helps to maintain some coolant movement by
convection and to also cool the enginecompartment to avoid fuel-line
vapor lock.

Notebooks, are a very different case, none are liquid cooled and
the temperature levels and differences between coolant and
components are not so extreme. Nor are you constrained by the
boiling point of the coolant and the batteries are not going
to vapor lock.

If you are worried about your Pismo:

1) Leave your screen up for a few minutes after shutdown if it seems
   unusually hot (frankly mine has never been anywhere near as hot as
   it gets just idling in MacOS -- fire up a DVD and you could roast
   marshmellows). Convection through the keyboard is the primary cooling
   mechanism, the fan isn't even secondary (and if it did run after
   shutdown, it would have very limited effectiveness with the screen
   down).

OR:

2) You are free to not run Linux, but you better not run Darwin either.
   Darwin also doesn't have any thermal management for any of the
   PowerBooks. The high-level abstract classes for thermal management,
   including fan speed control, are in the new Darwin IOKit, but no
   machine specific implementations -- yet. Even with the thermal
   management of the fan speed, all you gain is a bit of noise and perhaps
   power reduction for transient thermal increases. If the increased
   thermal load is sustained, the fan will eventually have to run full
   speed, which is what the PMU appearently does anyway as a fail-safe.


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Re: Pismo status

[Sergio Brandano]

 I do not know why I am wasting time with this issue. Anyway, I have a
 very different experience on cooling both cars and computers. All the
 cars I happen to see do run the fan after shutdown (I can clearly
 hear the quiet after shutdown, then the sound of the fan after a few
 seconds). This is probably due to a different design for countries
 with a warm weather, as you report otherwise. Concerning computers,
 and Linux, it is running this OS that the situation improved, as far
 as Intel processors are concerned. I can say that the cpus, before
 the advent of the caged P-II, where so cold that I could safaly touch
 them. This was, again, using Linux. Using MS-Windows, instead, I
 could *not* do the similar thing for sure. And I have been using
 Intel processors for a long, long time. I have a very different
 experience with PPC. I purchased my first one last summer, and it is
 damn hot. How is that Linux does not help here? How is that PPC is
 claimed to be cooler than Intel? The bla-bla takes a different shape
 when you touch with the finger eh? I also experienced that GNOME's
 screen saver pumps up the CPU to 100% when it is active. If the
 PowerBook is cool before triggering the screen saver, it gets boiling
 hot (with fan spinning) after 30mins. Why is that? I would expect it
 to shut the display off and similar things, rather than deliberately
 trying to fry my baby. Anyway, I am done with this topic.

 Good luck you all.

 Sergio

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Re: Pismo status

[Michel Dänzer]

Sergio Brandano wrote:

I'm not going to comment on your flamebait other than if you think Intel is
better than PowerPC, sell your Powerbook and stop complaining.


> I also experienced that GNOME's screen saver pumps up the CPU to 100% when
> it is active. If the PowerBook is cool before triggering the screen saver,
> it gets boiling hot (with fan spinning) after 30mins. Why is that? I would
> expect it to shut the display off and similar things, rather than
> deliberately trying to fry my baby.

Just turn off the screensaver in the GNOME control center and it will behave
exactly like you expect it to.


Michel


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Re: Pismo status

[David A. Gatwood]

On Sat, 20 May 2000, Sergio Brandano wrote:

>  I do not know why I am wasting time with this issue. Anyway, I have a
>  very different experience on cooling both cars and computers. All the
>  cars I happen to see do run the fan after shutdown (I can clearly
>  hear the quiet after shutdown, then the sound of the fan after a few
>  seconds). This is probably due to a different design for countries
>  with a warm weather, as you report otherwise. Concerning computers,
>  and Linux, it is running this OS that the situation improved, as far
>  as Intel processors are concerned. I can say that the cpus, before
>  the advent of the caged P-II, where so cold that I could safaly touch
>  them. This was, again, using Linux. Using MS-Windows, instead, I
>  could *not* do the similar thing for sure. And I have been using
>  Intel processors for a long, long time. I have a very different
>  experience with PPC. I purchased my first one last summer, and it is
>  damn hot. How is that Linux does not help here? How is that PPC is
>  claimed to be cooler than Intel?

Don't compare Apples and Oranges.  You're comparing a Pentium II to a G3.
A PII is somewhere near a PPC 604 in terms of speed.  If you touch a 604
heat sink, in my experience, it's luke warm even after running for several
hundred days continuously under linux.  Been there, done that.

For a fair comparison to the G3, you need to consider at least a Pentium
III (at about half again faster clock speed ;-).

> I also experienced that GNOME's
>  screen saver pumps up the CPU to 100% when it is active. If the
>  PowerBook is cool before triggering the screen saver, it gets boiling
>  hot (with fan spinning) after 30mins.

Oh, this is a PowerBook.  The machine gets hot for a lot of reasons, not
just the CPU.  Video chips generate lots of heat, as does your hard drive,
as do the power regulation circuits on the various boards.  In fact, I'd
expect the cpu to be one of the cooler devices, normally.  ;-)


>  Why is that? I would expect it
>  to shut the display off and similar things, rather than deliberately
>  trying to fry my baby. Anyway, I am done with this topic.

When the fan kicks on, you're still nowhere near a dangerous operating
temperature....  The fan usually kicks on when there's insufficient heat
dissipation from the bottom of the case (e.g. sitting on a bed, couch,
etc.).  I've never had a fan kick on if the machine was on a hard surface,
and that's with the LapBurner (err... I mean WallStreet ;-).

You can always turn off the gnome screensaver and just use xset to turn on
screen blanking, though.  :-)


Later,
David

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Re: Pismo status

[Sven LUTHER]

On Sat, May 20, 2000 at 10:52:31PM -0700, David A. Gatwood wrote:
> On Sat, 20 May 2000, Sergio Brandano wrote:
>
> >  I do not know why I am wasting time with this issue. Anyway, I have a
> >  very different experience on cooling both cars and computers. All the
> >  cars I happen to see do run the fan after shutdown (I can clearly
> >  hear the quiet after shutdown, then the sound of the fan after a few
> >  seconds). This is probably due to a different design for countries
> >  with a warm weather, as you report otherwise. Concerning computers,
> >  and Linux, it is running this OS that the situation improved, as far
> >  as Intel processors are concerned. I can say that the cpus, before
> >  the advent of the caged P-II, where so cold that I could safaly touch

Well, ...

not so long ago i fried a Pentium 200 because i forgot to connect the fan ...

and believe me, it was not cold when i touched it, ...

> >  them. This was, again, using Linux. Using MS-Windows, instead, I
> >  could *not* do the similar thing for sure. And I have been using
> >  Intel processors for a long, long time. I have a very different
> >  experience with PPC. I purchased my first one last summer, and it is
> >  damn hot. How is that Linux does not help here? How is that PPC is
> >  claimed to be cooler than Intel?
>
> Don't compare Apples and Oranges.  You're comparing a Pentium II to a G3.
> A PII is somewhere near a PPC 604 in terms of speed.  If you touch a 604
> heat sink, in my experience, it's luke warm even after running for several
> hundred days continuously under linux.  Been there, done that.

Also it depends if your are using a tower or desktop casing, instead of a
laptop. The laptop is tiny, has no big cooling box and i think most heat of
your laptop comes from your harddisk, graphic chip, memory and DVD drive.

> For a fair comparison to the G3, you need to consider at least a Pentium
> III (at about half again faster clock speed ;-).

well, i think the pIII are less watt hungry, since they are done in a smaller
process. IBM is advertissing their G3 as using less than 6Watss, while PII
used more than 20/30 watts, not to compare with the fast athlons which use 50
watts and up. and since used watts are dissipated more or less into heat, ...

Friendly,

Sven LUTHER

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Re: Pismo status

[Sergio Brandano]

 ... I am glad I have the PB. I like it. No, better, I love it!
 And it feels so good at winter time. But sometimes my hands (and
 legs) feel way too warm... It is not a matter of heavy work when it
 happens, as word processing is not that demanding for a CPU. 6W
 rather than 30W sounds good, but I have no experience on P-III
 laptops, so I really could not tell about how they feel like.
 It seems that they have the fan ON all the time, that is also more
 silent than the PB one. Sony's VAIO is also slimmer than the PB...

> not so long ago i fried a Pentium 200 because i forgot to connect
> the fan ...

 Using Linux?

 SB

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Re: Pismo status

[Sven LUTHER]

On Mon, May 22, 2000 at 02:44:18PM +0000, Sergio Brandano wrote:
>
>  ... I am glad I have the PB. I like it. No, better, I love it!
>  And it feels so good at winter time. But sometimes my hands (and
>  legs) feel way too warm... It is not a matter of heavy work when it
>  happens, as word processing is not that demanding for a CPU. 6W
>  rather than 30W sounds good, but I have no experience on P-III

Well the PIII mobile cpus (which by the way are not full cpus compared to
their desktop counterpart) are done in a smaller process and should be below
20Watt, i think, maybe around 18Watt (at the smaller sppeds naturally).

>  laptops, so I really could not tell about how they feel like.
>  It seems that they have the fan ON all the time, that is also more
>  silent than the PB one. Sony's VAIO is also slimmer than the PB...
>
> > not so long ago i fried a Pentium 200 because i forgot to connect
> > the fan ...
>
>  Using Linux?

Well, yes, ... what else ?

Friendly,

Sven LUTHER

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Re: Pismo status

[Sergio Brandano]

>>  Using Linux?

>Well, yes, ... what else ?

 The Pentium implements the sleep function, as far as I remember,
 and Linux supports it. You probably had a broken kernel.

 (I am assuming a ``normal'' use of the computer, or course, where one
 writes, stops, thinks, then writes again and so forth.)

 SB

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Re: Pismo status

[Sven LUTHER]

On Mon, May 22, 2000 at 03:01:42PM +0000, Sergio Brandano wrote:
>
> >>  Using Linux?
>
> >Well, yes, ... what else ?
>
>  The Pentium implements the sleep function, as far as I remember,
>  and Linux supports it. You probably had a broken kernel.

Well, i was just installing debian on the box, it was not supposed to go to
sleep, ... and rather busy unpacking stuff also, ...

Friendly,

Sven LUTHER

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Re: Pismo status

[Sergio Brandano]

> Well, i was just installing debian on the box, it was not supposed
> to go to sleep, ... and rather busy unpacking stuff also, ...

 That task keeps the Hard Disk fairly busy and the CPU mostly quiet.
 You were probably doing something else with that CPU before
 installing Debian. Anyway, let see if we can improve the situation
 and have the pmud package for Debian PPC.

 SB

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Re: Pismo status

[Sven LUTHER]

On Mon, May 22, 2000 at 03:16:44PM +0000, Sergio Brandano wrote:
>
> > Well, i was just installing debian on the box, it was not supposed
> > to go to sleep, ... and rather busy unpacking stuff also, ...
>
>  That task keeps the Hard Disk fairly busy and the CPU mostly quiet.
>  You were probably doing something else with that CPU before

Well, maybe on your fast G3 it does not strain the CPU to much, but on a slow
p 200, i think gunziping lots of files is going to use some CPU, at least
enough to not let the kernel put the cpu to sleep.

but lets stop this thread here also, ...

>  installing Debian. Anyway, let see if we can improve the situation
>  and have the pmud package for Debian PPC.

Sure, ..

Friendly,

Sven LUTHER

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Re: Pismo status

[Michael Schmitz]

> >  installing Debian. Anyway, let see if we can improve the situation
> >  and have the pmud package for Debian PPC.
>
> Sure, ..

Speaking of which: can someone point me to the URL for the 0.6 pmud
source? If no one else is interested, I'd package it for Debian.

	Michael


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Re: Pismo status

[Michel Dänzer]

Michael Schmitz wrote:
>
> > >  installing Debian. Anyway, let see if we can improve the situation
> > >  and have the pmud package for Debian PPC.
> >
> > Sure, ..
>
> Speaking of which: can someone point me to the URL for the 0.6 pmud
> source?

Look at http://www.dcs.qmw.ac.uk/~sb/PowerBook.html


> If no one else is interested, I'd package it for Debian.

That'd be nice.


Michel


--
Me? A skeptic? Can you prove it?
______________________________________________________________________________
Earthling Michel Dänzer (MrCooper)  \  CS student and free software enthusiast
Debian GNU/Linux (powerpc,i386) user \   member of XFree86, Team *AMIGA*, AUGS

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Re: Pismo status

[Sergio Brandano]

>Speaking of which: can someone point me to the URL for the 0.6 pmud
>source? If no one else is interested, I'd package it for Debian.

 Just visit my page:
 http://www.dcs.qmw.ac.uk/~sb/PowerBook.html

 Look under the "Power Management" section. You will find the
 intructions for a Debian installation and relative init file (written
 by me). Please contact Stephan Leemburg (stephan@jvc.nl) for it all.

 Sergio

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Re: Pismo status

[Michael Schmitz]

> >Speaking of which: can someone point me to the URL for the 0.6 pmud
> >source? If no one else is interested, I'd package it for Debian.
>
>  Just visit my page:
>  http://www.dcs.qmw.ac.uk/~sb/PowerBook.html

Just when I thought I'd seen all the Powerbook Linux pages :-) Thanks for
the pointer.

>  Look under the "Power Management" section. You will find the
>  intructions for a Debian installation and relative init file (written
>  by me). Please contact Stephan Leemburg (stephan@jvc.nl) for it all.

I'll send him all my patches - seems like there's been some changes in
asm/pmu.h for instance.

	Michael


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Re: Pismo status

[Timothy A. Seufert]

At 9:51 AM +0000 5/20/00, Sergio Brandano wrote:
>  I do not know why I am wasting time with this issue. Anyway, I have a
>  very different experience on cooling both cars and computers. All the
>  cars I happen to see do run the fan after shutdown (I can clearly
>  hear the quiet after shutdown, then the sound of the fan after a few
>  seconds). This is probably due to a different design for countries
>  with a warm weather, as you report otherwise.

My car (designed for a country with warm weather) does not do this.
Many cars aren't even capable of it: they don't have an electric
engine fan, choosing instead to run the fan off an engine accessory
drive belt, meaning that the fan can only run while the engine runs.

>  Concerning computers,
>  and Linux, it is running this OS that the situation improved, as far
>  as Intel processors are concerned. I can say that the cpus, before
>  the advent of the caged P-II, where so cold that I could safaly touch
>  them. This was, again, using Linux. Using MS-Windows, instead, I
>  could *not* do the similar thing for sure.

So you never did anything processor intensive under Linux, eh?

>  And I have been using
>  Intel processors for a long, long time. I have a very different
>  experience with PPC. I purchased my first one last summer, and it is
>  damn hot. How is that Linux does not help here? How is that PPC is
>  claimed to be cooler than Intel? The bla-bla takes a different shape
>  when you touch with the finger eh?

If you're talking about notebooks, the problem is that Apple doesn't
do a particularly good job of getting rid of heat.  They've been
getting better with recent models, but many of their notebooks just
don't have very good cooling systems and thus build up to a high
temperature easily.  There is a difference between temperature and
heat.

If you're talking about desktop machines where cooling systems are
much easier, you're nuts.  Look at the heatsink and fan on a Pentium
II, then look at the heatsink on a G3 (comparable processors; a G3 is
about as fast as the next speed grade up of PII, e.g. 266 G3 is about
equal to 300 PII).  Apple doesn't even have to put a fan on the
heatsink (all they need is airflow created by the power supply or
case fan), and it's a hell of a lot smaller than the PII heatsink.

>  I also experienced that GNOME's
>  screen saver pumps up the CPU to 100% when it is active. If the
>  PowerBook is cool before triggering the screen saver, it gets boiling
>  hot (with fan spinning) after 30mins. Why is that? I would expect it
>  to shut the display off and similar things, rather than deliberately
>  trying to fry my baby. Anyway, I am done with this topic.

If you try to use a graphically intensive screen saver to cool down
the machine, you're stupid.  Sorry, I can't help you with that.  But
if you do want to give the machine a rest when you're away, run pmud
instead (pmud = pmu daemon, search the mailing archives for info).

   Tim Seufert

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Re: Pismo status

[Ethan Benson]

[-- Attachment #1: Type: text/plain, Size: 1710 bytes --]

On Sun, May 21, 2000 at 02:01:25PM -0700, Timothy A. Seufert wrote:
[snip]

> >  Concerning computers,
> >  and Linux, it is running this OS that the situation improved, as far
> >  as Intel processors are concerned. I can say that the cpus, before
> >  the advent of the caged P-II, where so cold that I could safaly touch
> >  them. This was, again, using Linux. Using MS-Windows, instead, I
> >  could *not* do the similar thing for sure.
> 
> So you never did anything processor intensive under Linux, eh?

i think what he is refering to is when left idle an intel box running
linux will be MUCH cooler then it is when running MS-WinBloat.
apparently the linux kernel will issue a `hlt' instruction to the
processor when there is nothing to do, this puts the processor to
sleep or low power mode.  MS-Windows on the other hand always runs in
a very tight active loop keeping the processor running full tilt all
the time.  at least this is something i read somewhere feel free to
ignore/write off as total bullshi* ;-)

[snip]
> If you're talking about desktop machines where cooling systems are 
> much easier, you're nuts.  Look at the heatsink and fan on a Pentium 
> II, then look at the heatsink on a G3 (comparable processors; a G3 is 
> about as fast as the next speed grade up of PII, e.g. 266 G3 is about 
> equal to 300 PII).  Apple doesn't even have to put a fan on the 
> heatsink (all they need is airflow created by the power supply or 
> case fan), and it's a hell of a lot smaller than the PII heatsink.

then look at the heat sync on a G4 -- friggen monster about the size
of a video tape ;-)

[snip]

-- 
Ethan Benson
http://www.alaska.net/~erbenson/

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Re: Pismo status

[Timothy A. Seufert]

At 9:17 PM -0800 5/21/00, Ethan Benson wrote:

>then look at the heat sync on a G4 -- friggen monster about the size
>of a video tape ;-)

That particular heatsink was designed to allow the processor to
survive if the computer's main air circulation fan dies.  It doesn't
actually have to be that large for normal operation.  (G4 ZIF socket
upgrades for G3 Macs don't come with a huge heatsink as far as I
know, and they do fine.)

   Tim Seufert

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Re: Pismo status

[David A. Gatwood]

On Sun, 21 May 2000, Ethan Benson wrote:

> then look at the heat sync on a G4 -- friggen monster about the size
> of a video tape ;-)

Yes, but that is _all_ the cooling needed.  A PIII has a monster heat
sink, _and_ a cpu fan, _and_ a case fan, _and_....  ;-)


David

---------------------------------------------------------------------
A brief Haiku:

Microsoft is bad.
It seems secure at first glance.
Then you read your mail.


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Re: Pismo status

[Sven LUTHER]

On Fri, May 19, 2000 at 12:30:07PM +0000, Sergio Brandano wrote:
>
> >>  Sorry, I do not see your point.
> >>
> >>  My point is that if the CPU is piping hot, and you shutdown the
> >>  computer, no cooling is provided. This is wrong, as the fan has
> >>  nothing to do with the OS and it *must* spin until the temperature
> >>  reaches a safe level.
>
> >Well, the fan is there to remove the exess heat generated by a running CPU, if
> >you shut off the CPU, there will be no more exess heat generated, and the
> >existing heat will most assuredly be dissipated to less active cooling
> >mechanism. Since you cannot damage the CPU, or other pieces of the hardware,
> >this should cause no problem. And i think the G3 processor is not so hot
> >running, that it will be so much above the safe temperature state.
>
>  Ok Sven. You are convinced about your idea, but I am still skeptical.
>  In order to persuade me, I need a proof. Please perform this simple
>  experiment, then report the result. The experiment is as follows.
>  Have a nice and long trip with your car, then come back home, and
>  switch the engine off ensuring that the cooling fan is not spinning.
>  Let us know if your car starts again the next day.

well, i think the motor of your car is a lot heat producing and retaining than
the G3 cpu of your laptop, isn't it ?

>  If you prefer, you can perform the similar experiment with your brand new
>  PowerBook 500Mhz. Just run an intensive floating point application

If only i had one, ...

>  for a long time, then shutdown. Keep doing it every day, for a week
>  or so. Let us know it your jewel works fine at the end of it.

Ok, no problem it is your hardware, you do as you think is best, but still,
there were talks about powerbook case cooling without fan, so this could be
not so big a problem, unless you are using your laptop at noon in the sahara.

That said, i don't believe apple (as well as all the other laptop builders)
would release a laptop that would fry itself like that, ... they would be
facing lots of angry customer if it was so.

...

Another experiment you could try :

you use your laptop intensively as you said above, then before switching it
off, you put a thermometer on the cpu, or near it, and switch it off, you will
see how fast the temperature will drop ...

Anyway, lets stop this thread now, ...

Friendly,

Sven LUTHER

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Re: Pismo status

[David A. Gatwood]

On Sat, 20 May 2000, Sven LUTHER wrote:

> >  Ok Sven. You are convinced about your idea, but I am still skeptical.
> >  In order to persuade me, I need a proof. Please perform this simple
> >  experiment, then report the result. The experiment is as follows.
> >  Have a nice and long trip with your car, then come back home, and
> >  switch the engine off ensuring that the cooling fan is not spinning.
> >  Let us know if your car starts again the next day.

Um, there's a big difference there.  Your car is mechanical.  Computers
are not, other than the hard drive.  And excess heat probably does
contribute to stiction in hard drives, but that's about it.  When you stop
your car, oil drains out of the engine.  If the engine is still in an
expanded state from the heat, you're in deep you-know-what.  ;-)


> >  for a long time, then shutdown. Keep doing it every day, for a week
> >  or so. Let us know it your jewel works fine at the end of it.
>
> Ok, no problem it is your hardware, you do as you think is best, but
> still, there were talks about powerbook case cooling without fan, so
> this could be not so big a problem, unless you are using your laptop at
> noon in the sahara.

Yeah.  The powerbook case cools both through heat rising through gaps in
the keyboard and through the entire thing being basically one huge heat
sink.  :-)


> That said, i don't believe apple (as well as all the other laptop builders)
> would release a laptop that would fry itself

No, but they can fry eggs, or at least the wallstreets could.  :-)


David

---------------------------------------------------------------------
A brief Haiku:

Microsoft is bad.
It seems secure at first glance.
Then you read your mail.


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Re: Pismo status

[Worth]

On Thu, 18 May 2000, Sergio Brandano wrote:

>
>  There is one standard feature of automobiles that has not yet been
>  implemented for computers, namely if you switch off the computer the
>  cooling system should stay on until needed.

Actually it's old hat on mainframes, though that is mainly due to
numerous extremely hot chips with relatively small heat sinks in a
constrained plenum or manifold that depends upon high coolant flow.
And, on liquid cooled systems, to avoiding condensation problems.

>
>  (On my 101, I often hear the fan going on just when I need to shut
>  down. The fact is that when I want to shut down, I do not want to
>  wait for the fan, and I also put the screen down...

No need to wait for the fan, it's not the only cooling source, or
even the primary. The semiconductor junctions are already as hot as they
are going to get and are not producing any more heat. The surface of the
heat sink may have an upward transient at shutdown due to the loss of
airflow, but it's still cooler than those junctions or the bulk of the
heat sink.


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Re: Pismo status

[Sven LUTHER]

On Wed, May 17, 2000 at 10:15:24PM -0700, Timothy A. Seufert wrote:
> At 2:08 PM +0200 5/17/00, Sven LUTHER wrote:
> >On Wed, May 17, 2000 at 12:54:22PM +0200, Michael Schmitz wrote:
> >>  > Tim Wojtulewicz wrote:
> >>  > > No it's definitely supposed to have a fan.  It comes on in MacOS.
> >>  > > The problem is that the PMU is not fully supported yet, so it doesn't
> >>  > > understand that the processor is too hot.  I'm trying to find
> >>  >                       ^^^^^^^^^^^^^^^^^^^^
> >>  > Does this mean that I can damage the machine if I just run a high-load
> >>  > program?!?
> >>
> >>  I strongly doubt that. The PMU should handle this autonomously, regardless
> >>  of Linux support for the PMU.
> >
> >Also, i think the ppc cpu will halt itself when becoming too hot,
>
> No, it will not.
>
> The PowerPC 750 (G3) and 7400 (G4) can both fire off an interrupt
> when the on-die temperature sensor reading rises above a trigger
> value (or falls below a second trigger value).  This feature *could*
> be used by an operating system to slow down the CPU (through the

So this mean that the G3 and G4 cpus have both the equivalent of
speedstep/whatever that AMD & Intel are introducing as a big novelty ?

> instruction cache throttling feature) or halt it to prevent
> overheating.  However, there is no hardware feature which can halt
> the CPU without software control.

Are you sure about this ? did you already manage to burn out a ppc cpu like
you do when running a pentium without a fan ?

> >  and not let
> >itself burn. At elast it was so since the earlier 680x0 cpus.
>
> As far as I know none of the 680x0 CPUs even had an on-die
> temperature sensor, let alone a thermal shutdown feature.

I think to remember that the later 680X0 have, maybe not a temperature sensor,
but a way to halt themself before burning, ...

Friendly,

Sven LUTHER

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Re: Pismo status

[Timothy A. Seufert]

At 4:33 PM +0200 5/18/00, Sven LUTHER wrote:
>On Wed, May 17, 2000 at 10:15:24PM -0700, Timothy A. Seufert wrote:
>>  The PowerPC 750 (G3) and 7400 (G4) can both fire off an interrupt
>>  when the on-die temperature sensor reading rises above a trigger
>>  value (or falls below a second trigger value).  This feature *could*
>>  be used by an operating system to slow down the CPU (through the
>
>So this mean that the G3 and G4 cpus have both the equivalent of
>speedstep/whatever that AMD & Intel are introducing as a big novelty ?

Sort of.  The method is quite different.  I think AMD and Intel are
actually changing the core clock rate of the processor in response to
system conditions.  The 750 and 7400 can't do that.  Instead, they
can restrict the speed at which instructions can be fetched from the
I-cache into the prefetch queue, which in turn results in lower power
use (and of course lower performance) due to the dynamic power
management features of the 750 and 7400, which save power by
completely halting the clock going to idle functional units.

>>  instruction cache throttling feature) or halt it to prevent
>>  overheating.  However, there is no hardware feature which can halt
>>  the CPU without software control.
>
>Are you sure about this ? did you already manage to burn out a ppc cpu like
>you do when running a pentium without a fan ?

There is no mention of such a thing in the PowerPC 750 manual.

   Tim Seufert

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Re: Pismo status

[Tim Wojtulewicz]

On Wed, 17 May 2000, Timothy A. Seufert wrote:

>
> No, it will not.
>
> The PowerPC 750 (G3) and 7400 (G4) can both fire off an interrupt
> when the on-die temperature sensor reading rises above a trigger
> value (or falls below a second trigger value).  This feature *could*
> be used by an operating system to slow down the CPU (through the
> instruction cache throttling feature) or halt it to prevent
> overheating.  However, there is no hardware feature which can halt
> the CPU without software control.
>

So in other words, without a little bit of help from the OS, the fan won't
come on when it the temperature hits this trigger value.  The temperature
would of course, continue to rise.

> The normal mode is that MacOS controls the fan through the PMU.  The
> PMU is connected to a thermistor located somewhere on the
> motherboard.  MacOS scans the value of this thermistor every so often
> and uses the fan to cool the machine if it's getting warm.  MacOS
> takes advantage of the speed control feature of the fan, so it won't
> crank the fan up to full speed if it doesn't have to.

Has any code been written for LinuxPPC that will let us monitor this
sensor?  I know there's a whole lm_sensors package for i386 and the like,
but is there something like this for us?

> If MacOS fails to turn the fan on for some reason, the PMU acts as a
> backup controller -- it is also monitoring the thermistor and will
> force the fan to turn on at full speed if a moderately high (but not
> yet unsafe) temperature is reached.
>
> If the PMU's fan override fails to stop the computer's temperature
> from rising, and the temperature begins to approach dangerous levels,
> the PMU will simply shut the machine down without asking.  (Most Macs
> since the Mac II have had a thermal shutdown feature like this,
> including the desktops.)
>
> So, at least for 101, the fan should still come on without operating
> system support, followed by an abrupt shutdown if the computer gets
> way too hot.

Yes, my fan does come on Linux.  But it takes a long time, and the case
gets very warm before it does.  I assume this means the PMU has finally
decided it's too hot and turned on the fan.  I know it's most likely not
Linux doing it.

> The current PowerBook G3, 102 (the one with FireWire, popularly and
> in this case correctly known as "Pismo"), does have a different PMU
> than 101.  Apple did a major upgrade to the PMU used with all Core99
> chipset machines, 102 included.  But it's fairly unlikely that Apple
> changed the fan control technique very much.

Yes, I had heard they upgraded the PMU, but I wasn't aware of how much
they had changed it.  Is it just a matter of knowing some extra bits we
can switch on and off in the PMU, or is it more than that?

Tim


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Re: Pismo status

[Timothy A. Seufert]

At 7:48 AM -0700 5/18/00, Tim Wojtulewicz wrote:
>On Wed, 17 May 2000, Timothy A. Seufert wrote:
>
>>
>>  No, it will not.
>>
>>  The PowerPC 750 (G3) and 7400 (G4) can both fire off an interrupt
>>  when the on-die temperature sensor reading rises above a trigger
>>  value (or falls below a second trigger value).  This feature *could*
>>  be used by an operating system to slow down the CPU (through the
>>  instruction cache throttling feature) or halt it to prevent
>>  overheating.  However, there is no hardware feature which can halt
>>  the CPU without software control.
>>
>
>So in other words, without a little bit of help from the OS, the fan won't
>come on when it the temperature hits this trigger value.  The temperature
>would of course, continue to rise.

This die temperature sensor has nothing to do with the PowerBook's
fan.  It's built into all PPC 750 and 7400 CPUs.

Apple could use the die sensor to control the fan, but instead they
use a sensor on the motherboard of the PowerBook, as the fan is
really intended to ensure that the ambient temperature inside the
whole PowerBook doesn't get too hot.  This because there are actually
things which are much more sensitive to overheating than the CPU,
like the hard drive.

>Has any code been written for LinuxPPC that will let us monitor this
>sensor?  I know there's a whole lm_sensors package for i386 and the like,
>but is there something like this for us?

For some PowerBooks / PMU versions, I think so.  We will probably get
full support for things like this when Apple puts it into Darwin/OS X.

>Yes, I had heard they upgraded the PMU, but I wasn't aware of how much
>they had changed it.  Is it just a matter of knowing some extra bits we
>can switch on and off in the PMU, or is it more than that?

Probably more than that, but I don't know anything beyond the basic
fact that the PMU (both the hardware and its control program) got the
first major upgrade in years.

   Tim Seufert

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Re: Pismo status

[Tim Wojtulewicz]

[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
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On Wed, 17 May 2000, Albrecht [iso-8859-1] Dreß wrote:

> Tim Wojtulewicz wrote:
> > No it's definitely supposed to have a fan.  It comes on in MacOS.
> > The problem is that the PMU is not fully supported yet, so it doesn't
> > understand that the processor is too hot.  I'm trying to find
>                       ^^^^^^^^^^^^^^^^^^^^
> Does this mean that I can damage the machine if I just run a high-load
> program?!?

There won't be any damage to the machine.  The problem is that when the
processor reaches a certain temperature (one that is above limits) it puts
out a halt instruction.  This causes the machine to lock up.  The
protection against overheating is built into the processor (last time I
checked).  What should happen is that the OS should realize that the
processor is getting too warm, and turn on the fan before that limit is
reached.  Unfortunately, the temperature sensing code doesn't work so
well (or maybe something else), and the fan never comes on.

Don't worry about the machine, somewhere I heard the plastic case can
handle around 250 degrees F, so it's not in any danger of melting.

Tim


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Re: Pismo status

[Sergio Brandano]

> What should happen is that the OS should realize that the processor
> is getting too warm, and turn on the fan before that limit is
> reached.

 ... relying on the OS for cooling the CPU?
 What is the advantage of doing it?
 What happened to good-old control theory?

 Sergio

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Re: Pismo status

[Worth]

On Wed, 17 May 2000, Sergio Brandano wrote:

>
> > What should happen is that the OS should realize that the processor
> > is getting too warm, and turn on the fan before that limit is
> > reached.
>
>  ... relying on the OS for cooling the CPU?
>  What is the advantage of doing it?
>  What happened to good-old control theory?
>
>  Sergio
>
>
>

It's unlikely that the OS is involved in controlling the fan. To
depend upon the OS would be a very stupid design, as what would
happen if it goes into la-la land in a processor-intensive infinite
loop...? The PMU is a uproc with it's own firmware and should be
managing the fan, provided the fan isn't simply controlled
by a thermo-switch. However, there is no documentation to that
effect, but I haven't found any sign of fan control in the
Darwin drivers (which added some Core99 support in the last
update).

Others have complained of the fan being on all the time, my PB2K
500 seems to have its on quite often and it never gets anywhere near
as hot as it gets idling in MacOS (which can get hot enough to
cause sweaty palms when typing).

It is very important that you leave the screen up when the
system is on. Convection through the keyboard is a major part
of that case's cooling design, which is why MacOS does not give
you the option of not going into sleep when it is closed (Apple has
released a tech note on that). Also use hdparm to keep the disks
from running more than necessary, they generate a lot of heat,
particularly the DVD.

Beyond that, until Apple releases some definitive documentation --
yah, right -- you pays your money and you takes your chances...


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