Archived from groups: comp.sys.laptops (More info?)

Hallo,

I have an acer 4051 with centrino 1.5. Normally the fan doesn't work,
but when the computer works a little harder it turns on. A the beginig
of using my laptop it almost didn't turn on at all. But lately it has
been almost always on. Is is a normal symptom?

Being annoyed by constant turning on and off of the fan I turned it on
permanently. Will it somehow affect it's life expenditure?

best wishes

lmr

Archived from groups: comp.sys.laptops (More info?)

It may shorten the life of the fan.

Here's a thought: Most laptop CPUs are cooled by a liquid filled "heat
pipe" with a fan blowing over a heat-exchanger (radiator). Over time
(and it can happen in months) the fan and the fins of the heat exchanger
can become clogged .... seriously clogged, in some cases .... with
dust, and the thing needs to be taken apart and cleaned with a brush
and/or compressed air.

If it used to hardly ever turn on, but lately it's turning on often,
this may well be what is happeing to your unit.

[Sometimes, you can "blow out" the cooling unit without actually taking
things apart.]


lmr wrote:

> Hallo,
>
> I have an acer 4051 with centrino 1.5. Normally the fan doesn't work,
> but when the computer works a little harder it turns on. A the beginig
> of using my laptop it almost didn't turn on at all. But lately it has
> been almost always on. Is is a normal symptom?
>
> Being annoyed by constant turning on and off of the fan I turned it on
> permanently. Will it somehow affect it's life expenditure?
>
> best wishes
>
> lmr

Archived from groups: comp.sys.laptops (More info?)

"Barry Watzman" <WatzmanNOSPAM@neo.rr.com> wrote in message
news:428CCCDD.9010404@neo.rr.com...
Date: Thu, 19 May 2005 17:28:58 GMT

... Most laptop CPUs are cooled by a liquid filled "heat pipe" with
a fan blowing over a heat-exchanger (radiator)...

Hi Barry... You mention this a lot. I'm just curious though, do you
recall about when they started to do this? I suppose the type of CPU
makes all of the difference. I seriously doubt my two Toshiba 2595XDVD
should have a heat exchanger ('99 era). They use a Celeron 400MHZ if you
are curious.


Cheers!


______________________________________________
Bill (using a HP Pavilion 8655 & Windows 2000)
-- written and edited within Word 2000

Archived from groups: comp.sys.laptops (More info?)

lmr <m@m.pl> wrote:
: Hallo,

: I have an acer 4051 with centrino 1.5. Normally the fan doesn't work,
: but when the computer works a little harder it turns on. A the beginig
: of using my laptop it almost didn't turn on at all. But lately it has
: been almost always on. Is is a normal symptom?

Does the laptop itself seem slower than it used to? The computer will
sense the temperature of the CPU and turn on the fan to cool it when
it reaches a set temperature. The CPU tends to heat up when it "works
a little harder" as you noticed. Maybe the CPU is now working harder
all the time?

In Windows, hold down the keys CTRL-ALT-DEL at the same time to bring
up the task manager. You will see the CPU usage at the bottom of this
little window. If it holds at a high percentage while you are just
watching it and the computer is doing nothing else, perhaps you have a
spybot or something else running all the time making the CPU work.

Andrew
--
----> Portland, Oregon, USA <----
*******************************************************************
----> http://www.bizave.com <---- Photo Albums and Portland Info
----> To Email me remove "MYSHOES" from email address
*******************************************************************

Archived from groups: comp.sys.laptops (More info?)

BillW50 wrote:
> "Barry Watzman" <WatzmanNOSPAM@neo.rr.com> wrote in message
> news:428CCCDD.9010404@neo.rr.com...
> Date: Thu, 19 May 2005 17:28:58 GMT
>
> ... Most laptop CPUs are cooled by a liquid filled "heat pipe"
> with a fan blowing over a heat-exchanger (radiator)...
>
> Hi Barry... You mention this a lot. I'm just curious though, do you
> recall about when they started to do this? I suppose the type of CPU
> makes all of the difference. I seriously doubt my two Toshiba 2595XDVD
> should have a heat exchanger ('99 era). They use a Celeron 400MHZ if
> you are curious.
>
>
> Cheers!
>
>
> ______________________________________________
> Bill (using a HP Pavilion 8655 & Windows 2000)
> -- written and edited within Word 2000

Heat pipes started in a big way with the P4 2+Ghz CPUs due to heat
generation that mimics industrial furnaces. The traditional fan/heat
sink would of necessity be too large to fit in the case. Look at the
3+Ghz P4 laptops, if you can find one any more, with the heat pipe air
exchanger arranged across the entire rear panel. The heat transfer is
an evaporation/condensation cycle with capillary flow. For quick
background on heat pipes see http://www.cheresources.com/htpipes.shtml
or google for more technical resouces.

Q

Archived from groups: comp.sys.laptops (More info?)

Quaoar <quaoar@tenthplanet.net> wrote:
: Heat pipes started in a big way with the P4 2+Ghz CPUs due to heat
: generation that mimics industrial furnaces. The traditional fan/heat
: sink would of necessity be too large to fit in the case. Look at the
: 3+Ghz P4 laptops, if you can find one any more, with the heat pipe air
: exchanger arranged across the entire rear panel.

But the Pentium M (part of Centrino) CPU doesn't get that hot so
probably doesn't use heat pipes, right? And the OP was using a
Pentium M (just to get back to the original post).

Andrew
--
----> Portland, Oregon, USA <----
*******************************************************************
----> http://www.bizave.com <---- Photo Albums and Portland Info
----> To Email me remove "MYSHOES" from email address
*******************************************************************

Archived from groups: comp.sys.laptops (More info?)

Andrew wrote:
> Quaoar <quaoar@tenthplanet.net> wrote:
>> Heat pipes started in a big way with the P4 2+Ghz CPUs due to heat
>> generation that mimics industrial furnaces. The traditional fan/heat
>> sink would of necessity be too large to fit in the case. Look at the
>> 3+Ghz P4 laptops, if you can find one any more, with the heat pipe
>> air exchanger arranged across the entire rear panel.
>
> But the Pentium M (part of Centrino) CPU doesn't get that hot so
> probably doesn't use heat pipes, right? And the OP was using a
> Pentium M (just to get back to the original post).
>
> Andrew

Heat pipes are far more efficient for CPU cooling than is the
traditional fan/heatsink. Not only are they more efficient, but the
heap pipe attachment to the CPU is small and compact and with more
efficient CPUs the heat exchanger is also small and can be placed in any
"leftover" space. The radial fans are also compact and fairly quiet.
Designers now use heat pipes in almost every laptop since it gives them
more design flexibility in thinner cases. The heat pipe can function
without or with minimal fan for a small heat load on lower speed CPUs.
That won't work on the P4 since it is generating significant heat even
at idle. Back to the Centrino/Pentium M, yes it is likely that it has a
heat pipe of one or two tubes.

Because of the way the the heat pipe air exchanger is designed with low
clearance fins surrounding the pipes to maximize heat rejection, the
exchanger invites plugging with fibers over time. On the P4 this can
result in a sudden thermal shutdown since the fan is always running and
the user becomes accustomed to the noise and doesn't notice that the fan
is running faster over time. The OPs observation is consistent with a
heat exchanger that is becoming obstructed, although there are other
reasons like more intensive use that can make the fan run harder, or
higher ambient temperature as summer approaches that raises the
temperature vs. load curve making the fan run harder.

The routine maintenance solution is simple: blow back through the
exchanger from the exit with computer dust cleaner or compressed air.
The fan should be restrained with a paper clip to prevent overspeed
damage. This will remove minor accumulations through the fan inlet.
More serious plugging as a mat resembling felt can be fixed only by
opening the case and physically removing the material. Sony Vaio P4
laptops are notorious for requiring physical removal since the fan
inlets do not have a screen but only simple slots in the case that pass
everything in the air. Other vendors install a metal screen that is
effective in removing the bulk of the fibers before they get a chance to
plug the exhanger.

I might have answered your question somewhere in this ...

Q

Archived from groups: comp.sys.laptops (More info?)

They stared doing it a number of years ago, at least on higher end
models. I remember around 2000 or 2001 looking at a brochure for a
high-end Toshiba (don't remember if it was a portege or tecra, but it
was not a Satellite), and they were doing it then. Also, my 2805's (I
have several), which are Satellites, have this, as does the 1415 and the
A45. The 2805's are 2001 vintage. So the practice is at least 4 years
old, perhaps older. I don't mean to imply that it's universal, it's
not, but I'd say that in current laptops, I do believe that far more
than half use such heat sinks for cooling. I would guess that it
started in Pentium II and III machines right about the 500MHz range.



BillW50 wrote:

> "Barry Watzman" <WatzmanNOSPAM@neo.rr.com> wrote in message
> news:428CCCDD.9010404@neo.rr.com...
> Date: Thu, 19 May 2005 17:28:58 GMT
>
> ... Most laptop CPUs are cooled by a liquid filled "heat pipe" with
> a fan blowing over a heat-exchanger (radiator)...
>
> Hi Barry... You mention this a lot. I'm just curious though, do you
> recall about when they started to do this? I suppose the type of CPU
> makes all of the difference. I seriously doubt my two Toshiba 2595XDVD
> should have a heat exchanger ('99 era). They use a Celeron 400MHZ if you
> are curious.
>
>
> Cheers!
>
>
> ______________________________________________
> Bill (using a HP Pavilion 8655 & Windows 2000)
> -- written and edited within Word 2000
>

Archived from groups: comp.sys.laptops (More info?)

I think that you underestimate the issues of dissipating power from even
a "low power" CPU. The use of heat pipes started long before any of the
current generation of laptops. A CPU die is only about one-quarter to
one-half inch square by perhaps .10 inches thick. Some desktop P4's can
dissipate over 120 watts in that space, but even a 20 or 30 watt CPU
presents enormous thermal management problems when that 20 or 30 watts
is created entirely in a silicon wafer whose total volume is well under
..025 cubic inches.


Andrew wrote:

> Quaoar <quaoar@tenthplanet.net> wrote:
> : Heat pipes started in a big way with the P4 2+Ghz CPUs due to heat
> : generation that mimics industrial furnaces. The traditional fan/heat
> : sink would of necessity be too large to fit in the case. Look at the
> : 3+Ghz P4 laptops, if you can find one any more, with the heat pipe air
> : exchanger arranged across the entire rear panel.
>
> But the Pentium M (part of Centrino) CPU doesn't get that hot so
> probably doesn't use heat pipes, right? And the OP was using a
> Pentium M (just to get back to the original post).
>
> Andrew
> --
> ----> Portland, Oregon, USA <----
> *******************************************************************
> ----> http://www.bizave.com <---- Photo Albums and Portland Info
> ----> To Email me remove "MYSHOES" from email address
> *******************************************************************
>