So what if thermal compound spreads?

"Matt" wrote in message
...
QBall wrote:
"Johannes H Andersen" wrote in message
...


Matt wrote:

Conor wrote:

In article ,
says...


CrackerJack wrote:


What exactly is the problem if too much cpu compound is put on the
core and it gets squashed out onto the surrounding area?

Apart from looking messy, is there any real problem with this?

I propose this answer:

1) If the compound is not too viscous, and the heatsink is clamped on
with some force, and you apply enough compound, the thickness of the
layer of compound does not depend on the amount applied, which is to

say

that the excess gets squeezed out.

2) Thermal compounds are not electrically conductive.

3) Some thermal compounds (notably those containing silver compounds)
have capacitative properties that can be problemmatic if compound
gets
between the chip's leads.

4) If you use a compound that doesn't have the problemmatic

capacitative

properties and is not too viscous, in general it won't hurt to use
too

much.


1) WRONG
2) WRONG
3) If 3 is true then 2) is wrong. You've just proved that yourself.
4) WRONG.


Your reply is practically content-free.

Please start with this: In what way does 3 contradict 2?

Apart from the above, the word you're looking for is 'dielectric'. Look
up any elementary physics text book.



Hehe ..... LOL
The contemporary edukation system has a lot to answer for.
Bad spelling is so freaking irritating.


What was misspelled?


Dielectric was 'dialectric' - like dialectic !

On Sun, 11 Apr 2004 20:26:53 +0100 As truth resonates honesty Lem
wrote :

Paul Hopwood wrote:

I realised he could have meant either, so asked for
elaboration. Actually some thermal compund is electrically
conductive too,

Any of the stuff that's filled with metallic particles is
potentially electrically conductive.

Please name one.

Arctic Silver is capacitive, rather than conductive, but the
same applies in terms of application. Their instructions
state:

"While much safer than electrically conductive silver and
copper greases, Arctic Silver should be kept away from
electrical traces, pins, and leads. While it is not
electrically conductive, the compound is slightly capacitive
and could potentially cause problems if it bridges two
close-proximity electrical paths.)"

I wouldn't doubt there are other compounds around which are
electrically conductive.


Hiya Paul. And now for something completely different .... Dan
compares toothpaste and Vegemite/Marmite to Artic Silver and finds
that both are actually better! At least they are until they dry
out.

http://www.dansdata.com/goop.htm

Dan is, of course, also the author of How To destroy Your Computer.
http://www.dansdata.com/sbs3.htm

I can believe it.There's lot's of Hype about.
I bought this cooler for my O/C AMD XP 1800,
MicroFlow2 SPA07B2 (Skt A)
http://tinyurl.com/ybtn

look at the price

and it came with it's own tube of,"Artic" silver.So the whole
kit-and-kaboodle was actually less than the cost one tube
of,"Genuine","Artic Silver".
Even under my heaviest gaming loads it rarely goes above 40 Deg C and
trust me I give my system,"Hammer".
I did polish the bottom of the HS but the copper centre really does
the biz anyway.

As we speak Idle temps are,

37 Deg C

Running @ 143/143


As summer comes I expect it to hit 50 Deg C,but then that's nowt for
an AMD and the ting is near silent as well

This has to be the bargain of the year IMNSHO :P



--
Free Windows/PC help,
http://www.geocities.com/sheppola/trouble.html
email shepATpartyheld.de
Free songs to download and,"BURN" :O)
http://www.soundclick.com/bands/8/nomessiahsmusic.htm

QBall wrote:
"Johannes H Andersen" wrote in message
...


Matt wrote:

Conor wrote:

In article ,
says...


CrackerJack wrote:


What exactly is the problem if too much cpu compound is put on the
core and it gets squashed out onto the surrounding area?

Apart from looking messy, is there any real problem with this?

I propose this answer:

1) If the compound is not too viscous, and the heatsink is clamped on
with some force, and you apply enough compound, the thickness of the
layer of compound does not depend on the amount applied, which is to

say

that the excess gets squeezed out.

2) Thermal compounds are not electrically conductive.

3) Some thermal compounds (notably those containing silver compounds)
have capacitative properties that can be problemmatic if compound gets
between the chip's leads.

4) If you use a compound that doesn't have the problemmatic

capacitative

properties and is not too viscous, in general it won't hurt to use too

much.


1) WRONG
2) WRONG
3) If 3 is true then 2) is wrong. You've just proved that yourself.
4) WRONG.


Your reply is practically content-free.

Please start with this: In what way does 3 contradict 2?

Apart from the above, the word you're looking for is 'dielectric'. Look
up any elementary physics text book.



Hehe ..... LOL
The contemporary edukation system has a lot to answer for.
Bad spelling is so freaking irritating.



Yeah, and don't you hate it when somebody replies and quotes a bunch of
material that is irrelevant to the point he is supposedly making?

"CrackerJack" wrote in message
...
What exactly is the problem if too much cpu compound is put on the
core and it gets squashed out onto the surrounding area?

Apart from looking messy, is there any real problem with this?

Prehaps this thread should be retitled "Much ado about nothing"?

"baskitcaise" wrote in message
...
Max wrote:

Which one?


I do know that artic silver 1 is slightly conductive, but the more
worrying
thing is the capacitance if it gets too close to contacts.

Good point, at the frequencies computers run at even a small capacitance
could be as harmful as a direct connection.
I once wire wrapped a computer and missed the input pin by one,
the inductantance caused it to work for a few seconds before failing.
Similar for capicitance, high frequencies fo through a capacitor as if it is
not there.



http://www.arcticsilver.com/arctic_s...structions.htm

--
Mark
Iligitimi Non Carborundum!
Twixt hill and high water, N.Wales, UK

On Mon, 12 Apr 2004 14:22:37 GMT, kony wrote:

On Mon, 12 Apr 2004 13:19:12 GMT, JT wrote:

I don't think he is referring to damage by static. I think there
is something "bad" about even a trace of grease like that from a
finger. I don't know why this is though.

Can anyone enlighten me (gently)?

Short term, skin oils are a poor heat conductor, so interfere with heat
transfer from cpu to heatsink. Long term most peoples skin oils are acidic
or salty enough to cause corrosion, which is also not a good thing to have
between a cpu and a heatsink

JT

Nonsense. NOBODY has enough oil on their fingers to significantly cause
corrosion or degrade the cooling efficiency. Now maybe if someone had
just finished picking their nose or painting a fence...

Simple experiment. Take a clean, shiny sheet of copper or brass. Make sure
it is clean. Use alcohol or the cleaner of your choice to ensure it is oil
free and clean. Now take your nice clean finger and touch the center of the
metal. Leave this metal somewhere that it won't be disturbed for a couple
weeks. See the discoloration? That is corrosion. That is enough to reduce
heat transfer, although not catastrophically. It is slow acting, but it
does happen. Doesn't take much corrosion to interfere with cooling. Because
it acts over time, it will take a while to cause a problem. Why take a
chance? Keep your fingers off the mating surface. If you are going to go to
the trouble of properly, why not keep your fingers out of the way.

BTW, some peoples skin oils are much more corrosive than others.

JT

In article m,
says...

Simple experiment. Take a clean, shiny sheet of copper or brass. Make sure
it is clean. Use alcohol or the cleaner of your choice to ensure it is oil
free and clean. Now take your nice clean finger and touch the center of the
metal. Leave this metal somewhere that it won't be disturbed for a couple
weeks. See the discoloration? That is corrosion.

Now lets make it a proper comparison by adding a heat source for
prolonged periods of time.


--
Conor

If you're not on somebody's **** list, you're not doing anything
worthwhile.

JT wrote:

On Mon, 12 Apr 2004 14:22:37 GMT, kony wrote:


On Mon, 12 Apr 2004 13:19:12 GMT, JT wrote:


I don't think he is referring to damage by static. I think there
is something "bad" about even a trace of grease like that from a
finger. I don't know why this is though.

Can anyone enlighten me (gently)?

Short term, skin oils are a poor heat conductor, so interfere with heat
transfer from cpu to heatsink. Long term most peoples skin oils are acidic
or salty enough to cause corrosion, which is also not a good thing to have
between a cpu and a heatsink

JT

Nonsense. NOBODY has enough oil on their fingers to significantly cause
corrosion or degrade the cooling efficiency. Now maybe if someone had
just finished picking their nose or painting a fence...


Simple experiment. Take a clean, shiny sheet of copper or brass. Make sure
it is clean. Use alcohol or the cleaner of your choice to ensure it is oil
free and clean. Now take your nice clean finger and touch the center of the
metal. Leave this metal somewhere that it won't be disturbed for a couple
weeks. See the discoloration? That is corrosion. That is enough to reduce
heat transfer, although not catastrophically. It is slow acting, but it
does happen. Doesn't take much corrosion to interfere with cooling. Because
it acts over time, it will take a while to cause a problem. Why take a
chance? Keep your fingers off the mating surface. If you are going to go to
the trouble of properly, why not keep your fingers out of the way.


I agree that touching the surface is bad (could lead to electrostatic
discharge in the chip etc). But in all fairness, any minute oil you
have might eventually be dissipated within the compound.

When installing IC's, hold them by the edges and don't touch the pins.
Make sure you are grounded too.

On Tue, 13 Apr 2004 15:17:41 GMT, JT wrote:
Short term, skin oils are a poor heat conductor, so interfere with heat
transfer from cpu to heatsink. Long term most peoples skin oils are acidic
or salty enough to cause corrosion, which is also not a good thing to have
between a cpu and a heatsink

JT

Nonsense. NOBODY has enough oil on their fingers to significantly cause
corrosion or degrade the cooling efficiency. Now maybe if someone had
just finished picking their nose or painting a fence...

Simple experiment.

.... too simple to be applicable.

Take a clean, shiny sheet of copper or brass. Make sure
it is clean.

So far so good.

Use alcohol or the cleaner of your choice to ensure it is oil
free and clean.

So long as you do that to the CPU and heatsink too...


Now take your nice clean finger and touch the center of the
metal.

Here's where you go wrong.
That should read "now take your nice clean finger and put heatsink
compound on it and touch THAT to the metal, then take (some other object)
and put a similar spot of compound on another area of the metal.

Leave this metal somewhere that it won't be disturbed for a couple
weeks. See the discoloration?

I have tried the "real thing", not the inappropriate test. I
install/uninstall/clean/inspect heatsinks all the time. They weren't
corroded. Your theory only applies to the exact situation you describe,
not to heatsinks and thermal compound.

That is corrosion. That is enough to reduce
heat transfer,

Sorry but your experiment had nothing to do with heat transfer, this last
part is a stretch based upon an already invalid test.


although not catastrophically. It is slow acting, but it
does happen.

that should read "although insignificantly". It serves no purpose to
embellish the situation. The key here is "significance". Plenty of
people, myself included, have applied compound with a finger, taken a
'sink off after a year or more and cleaned it, including a light polish,
and temps afterwards were, within the accuracy provided by the on-die
diode, the same. This corrosion you claim, which was not visible, did not
appear to happen at all, also had no measurable effect on temp, which
would tend to suggest that it didn't happen to any significant extent.

Doesn't take much corrosion to interfere with cooling. Because
it acts over time, it will take a while to cause a problem. Why take a
chance?

You may feel you're taking a chance because you're relying on an untested
theory based upon only a loosely related observation. What would that
bare clean copper do even if you didn't touch it with your finger? Try
putting some compound on a spot (not with your finger) then let enough
time elapse, remove the compound and examine, compare the covered area to
(the rest of the sheet).

Keep your fingers off the mating surface. If you are going to go to
the trouble of properly, why not keep your fingers out of the way.

BTW, some peoples skin oils are much more corrosive than others.

JT

Nope, nobody's skin oil is particularly corrosive, relatively speaking,
then dillute it in compound, and remove air.
Why try to invent problems where there aren't any?
A vague untested theory about a dissimilar situation is pointless.

On Tue, 13 Apr 2004 17:52:05 +0100, Conor wrote:

In article m,
says...

Simple experiment. Take a clean, shiny sheet of copper or brass. Make sure
it is clean. Use alcohol or the cleaner of your choice to ensure it is oil
free and clean. Now take your nice clean finger and touch the center of the
metal. Leave this metal somewhere that it won't be disturbed for a couple
weeks. See the discoloration? That is corrosion.

Now lets make it a proper comparison by adding a heat source for
prolonged periods of time.

Do it. You will see the corrosion happens faster.

The point was contaminants like skin oil may also cause corrosion which
should be avoided.

JT