17 Nov
1999
17 Nov
'99
7:24 a.m.
P.S.: When designing a new cooler element/radiator,
keep in mind that
silver is a way better thermal conductor than Al or Cu.
Not quite accurate, Hans.
Silver and Copper are way better thermal conductors than Alumin(i)um, but
there's not much to choose between the two of them.
17 Nov
17 Nov
7:47 a.m.
Besides the CPU, what other chips need to be chilled to over-clock? The
Cache?
----------------------------------------
Tired of Micro$oft???
Move up to a REAL OS...
######__ __ ____ __ __ _ __ #
#####/ / / / / __ | / / / / | |/ /##
####/ / / / / / / / / / / / | /###
###/ /__ / / / / / / / /_/ / / |####
##/____/ /_/ /_/ /_/ /_____/ /_/|_|####
# ######
("LINUX" for those of you
without fixed-width fonts)
----------------------------------------
Be a Slacker! http://www.slackware.com
Slackware Mailing List:
http://www.digitalslackers.net/linux/list.html
10:42 a.m.
Depending on what you jack the bus speed up to, you want to make sure that
the cache is cooled as well as your video processor. I have a 3dfx board
that I needed to put an aftermarket fan/heatsink on because it ran so hot.
The nice thing about the high-pressure gas setup I mentioned earlier is
that you can direct the vented gas on hot spots to help keep them cool...
Aaron
On Wed, 17 Nov 1999, Arfon Gryffydd wrote:
Besides the CPU, what other chips need to be chilled
to over-clock? The
Cache?
----------------------------------------
Tired of Micro$oft???
Move up to a REAL OS...
######__ __ ____ __ __ _ __ #
#####/ / / / / __ | / / / / | |/ /##
####/ / / / / / / / / / / / | /###
###/ /__ / / / / / / / /_/ / / |####
##/____/ /_/ /_/ /_/ /_____/ /_/|_|####
# ######
("LINUX" for those of you
without fixed-width fonts)
----------------------------------------
Be a Slacker! http://www.slackware.com
Slackware Mailing List:
http://www.digitalslackers.net/linux/list.html
18 Nov
18 Nov
6:19 a.m.
New subject: E.U.N.U.C.H. (Other Chips)
Besides the CPU, what other chips need to be chilled
to over-clock? The
Cache?
All ICs where you like to rise the clockspeed - if you just
change the multipier its just the CPU. An atempt to increas
the bus speed by more than 30 % is quite rare this day - especialy
with standard components (i.e. going from 100MHz to 133 MHz).
So if you don't push anything special, just go ahead. If looking
at actual PCs, the graphic cards may be a good second target,
especialy since most of the newer chips (TNT/TNT2/gForce/V3/G400)
allow to change the clockspeed (seperate for GPU and VRAM) by software.
(This is also a good area to revitalize an old socket 7 cooler
design - one has to do a new for a PII or K7 anyway :)
Gruss
H.
--
Stimm gegen SPAM: http://www.politik-digital.de/spam/de/
Vote against SPAM: http://www.politik-digital.de/spam/en/
Votez contre le SPAM: http://www.politik-digital.de/spam/fr/
Ich denke, also bin ich, also gut
HRK
17 Nov
17 Nov
10:40 a.m.
On Wed, 17 Nov 1999 Philip.Belben(a)pgen.com wrote:
Anyway, it seems to me that the way to go is:
1. Peltier chip between CPU and heatsink. Heatsink is a large block of copper.
2. Use a refrigerant cycle similar to a domestic freezer, but connect the
refrigerant circuit directly to holes bored in the heatsink block. No
intervening water circuit.
3. Of course, keep the refrigerant radiator well away from the system, and
supply it with plenty of fans...
4. Finally, try not to spill refrigerant if it's one of those chlorinated
organics that the environmentalists are always going on about. It won't do any
good (although a discussion of whether it does harm is decidedly off-topic), and
will be well-nigh impossible to replace...
One issue with copper is the cost. I can buy .5" x 4" aluminum barstock at
around $2.00 a foot (I'm sure our friends in Europe love these units of
measurement). It's also relatively easy to bore through with a
high-quality drill bit if cooled with running water. Also, if I happen to
screw up and drill through the side I don't cry as much...
For my current peltier-based setup, I have to use a coldplate against the
cpu itself because I'm using multiple TECs in the design. After getting
some help with actually arranging the different variables into a useable
equation, I was pleasantly surprised to find that the temperatures were
within +/- 3C of my calculations.
One last note about using a water-exchanger in this setup (and then I'll
shut-up, I promise), is that it's nice not to have to worry about cooling
the inside of the case too! Also, it doesn't sound like a jet-engine
starting up...the pump is more like the pleasant gurgle of an aquarium.
So off-topic it hurts,
Aaron
18 Nov
18 Nov
6:19 a.m.
New subject: E.U.N.U.C.H. (Cooling)
> P.S.: When designing a new cooler
element/radiator, keep in mind that
> silver is a way better thermal conductor than Al or Cu.
Not quite accurate, Hans.
Silver and Copper are way better thermal conductors
than Alumin(i)um, but
there's not much to choose between the two of them.
Ok Ok, but it's better :)
>From Kaye and Laby, 15th edition: (all figures in
watts per metre per kelvin)
At -100 Celsius: Al, 241; Cu, 420, Ag, 432.
Interestingly enough, at these low
temperatures Beryllium is pretty good at 367.
At 0 Celsius: Al, 236; Cu, 403; Ag, 428. Be has
fallen to 218, behind even Al.
At 100 Celsius:Al, back up to 240; Cu, 395; Ag, 422.
According to my numbers: AL 210 Cu 380 Ag 408 - just I have no expliciet
temperature named (and I'm somewhat confused, since I belived that lambda
is not depending on any temperature, but rather a coefficient(?) to determinate
the conductance (?) - otherwise you'd have to integrate lambda over the
temperaturerange within the object (remember, its w/mK, where K is dT))
Conclusion: Cu and Ag are over 60% better than Al; at
low temperatures Ag is
better by 2%; at higher temperatures its lead increases to 6% but is still
nothing to write home about.
Well 6% are still 6%, especialy if the difference in price isn't that big.
FWIW Gold is the only other metal that makes it above
200, and is between Cu and
Al in all cases.
Anyway, it seems to me that the way to go is:
1. Peltier chip between CPU and heatsink. Heatsink is a large block of copper.
Adds more and more heat - an infinite loop, where you have to add a bigger
part to the 'interchange' on the hot side, hust for transporting the
Peltiers own heat. I found it better to optimise the transport within the
interchange element (as with using Cu or Ag, and mor efficient flow
structures) than just adding a Peltier. It's not about geting the
target temperature as low as possible, but rather transporting away
ad much (thermal) power as possible - that will inherently keep the
target from overheating.
Also, if we just remove the heat to keep the device (and all parts)
not below environment temperature we avoide all probems with
condensation (word?). We don't have to isolate all cooled parts
wathertight. Saving again a lot of recurces.
2. Use a refrigerant cycle similar to a domestic
freezer, but connect the
refrigerant circuit directly to holes bored in the heatsink block. No
intervening water circuit.
3. Of course, keep the refrigerant radiator well away
from the system, and
supply it with plenty of fans...
Or just use water and a real _big_ radiator to expell the heat.
After all, it's again about radiation a specific amount of
thermal power - and this can be done by either a high delta-T
or just a biger surface (phi = lamda * S * delta-T / delta).
4. Finally, try not to spill refrigerant if it's
one of those chlorinated
organics that the environmentalists are always going on about. It won't do any
good (although a discussion of whether it does harm is decidedly off-topic), and
will be well-nigh impossible to replace...
Or best of all, just use a matter with excelent properies and
no risk - like water (we are talking about a small amount, so
no risk of drowning) - water has one of the best termal capacity
numbers and good qualities in conductiviety (Just to avoide
questions why it isn't used in frigdes - Water can't be compressed -
so it is hard to reach temperatures below the environment).
Conclusion: I belive that a 'soft' aproach can give the same
result in most situation without spending endless resources
to push a single idea solution (brute force).
Gruss
H.
BTW: I considere this total on topic, since these are the same
problems since computers exist (I've been trained on cooled
CPU systems in the late 70s).
--
Der Kopf ist auch nur ein Auswuchs wie der kleine Zeh.
H.Achternbusch
7:39 a.m.
New subject: E.U.N.U.C.H. (Cooling)
Beware !!!!!!!!!!!!!!!!!!!
Beryllium was mentioned here. Beryllium Oxide was used in the thermal
conduction stuff HF-transistors decades ago, but this ceramic stuff can
be quite lethal. If it breaks and you inhale a few microns of the dust
there off, lungcancer can almost be guarantied within a decade !!!!
Stay away from BEO !!!!!
Sipke de Wal
Hans Franke wrote:
At -100 Celsius: Al, 241; Cu, 420, Ag, 432.
Interestingly enough, at these low
temperatures Beryllium is pretty good at 367.
8:03 a.m.
New subject: E.U.N.U.C.H. (Cooling)
Sipke de Wal wrote:
Beware !!!!!!!!!!!!!!!!!!!
[snip]
Stay away from BEO !!!!!
It *is* incredibly nasty. Loral used to have a division which made Be
spheres (can you say "neutron reflector"?); they fabed them in the
same equipment used to fab plutonium 'pits' due to the inhalation
hazard.
--
Chris Kennedy
chris(a)mainecoon.com
http://www.mainecoon.com
PGP fingerprint: 4E99 10B6 7253 B048 6685 6CBC 55E1 20A3 108D AB97
8:13 a.m.
New subject: E.U.N.U.C.H. (Cooling)
Yes, by me.
It was a suspension so dust was not possible. I also have silicone grease
with BEO for apps. Used to do things like cunduction cooled tube amps and
Water cooled tube amps so I know that stuff is dangerous. Blocks of the
stuff would be machined in a special negative pressure room with HEPA
filters, operator is in class-A garb for protection. If an insulator with
good thermal propterties is required the choices are small.
It's still used for those SOT RF power transistors.
Allison
On Thu, 18 Nov 1999, Sipke de Wal wrote:
Beware !!!!!!!!!!!!!!!!!!!
Beryllium was mentioned here. Beryllium Oxide was used in the thermal
conduction stuff HF-transistors decades ago, but this ceramic stuff can
be quite lethal. If it breaks and you inhale a few microns of the dust
there off, lungcancer can almost be guarantied within a decade !!!!
Stay away from BEO !!!!!
Sipke de Wal
Hans Franke wrote:
At -100 Celsius: Al, 241; Cu, 420, Ag, 432.
Interestingly enough, at these low
temperatures Beryllium is pretty good at 367.
9086
days inactive
9087
days old
8 comments
7 participants
participants (7)
-
af-list＠is1.wfi-inc.com -
allisonp＠world.std.com -
arfonrg＠texas.net -
chris＠mainecoon.com -
Hans.Franke＠mch20.sbs.de -
Philip.Belben＠pgen.com -
sipke＠wxs.nl