PDA

View Full Version : SUB-ZERO temps harm the CPU!!!!!


SoNgOkO
10-06-02, 04:59 AM
Hey!!

Recently i posted in the CPU section of this forum and asked if SUB-ZERO temps can harm the CPU.

This are the answers that i got:

Skiing Squirrel
At those temps, you will have problems with your cache. I wouldnt run them that low.

PCphreak
One thing you'll first need to consider. Whenever you bring your CPU from room temperature down to -40/-30 each time you turn it on, your inducing a greater degree of thermal cycling than that of standard air cooling. It'll be even worse the colder you go. This thermal cycling will eventually stress the chip from the continuous contracting and expanding and lead to failure. You may find the cost of bringing your CPU down @ a -40 range isn't worth the performance you get from the little extra overclock.

Tiger
The contraction and expansion will not be a problem at the temps you envisage(-30-40). They become a problem at -100C.

crash893
hes is right there are benifits to such a cool temp but if you go to cold it will pull its self apart when it contracts


I need more feedback is temp about -30 till -40 really a prob for the CPU????

Thanx

Diggrr
10-06-02, 08:06 AM
Tiger's correct, there are many people who refrigerate their cpu and use TEC's and other methods to get their processor really cold, but most stop at -30C (some rare examples get to -50C).
The ones that use dry ice and Liquid Nitrogen a few too many times find out the bitter cost of being so extreme.

And silicon is a crystal that's quite a rigid structure (and very strong though brittle) but it's rigidity can cause it to fail at extreme expansion/contraction cycles.

SoNgOkO
10-06-02, 08:13 AM
So u think that running the CPU at -30 can do no harm to the CPU?????

Diggrr
10-06-02, 08:26 AM
Correct. I plan to get my own A/C system running and shoot for -50C myself.
Never seem to have time and money at the same time.

hooziewhatsit
10-07-02, 01:12 AM
I wouldn't recommend turning if off every night... and possibly starting hotter and gradually cooling it that low.

Daemonfly
10-07-02, 02:10 AM
I would also agree with the gradual cooling, then once you get stable temps, leave it on 24/7.

ssjwizard
10-07-02, 03:39 AM
if your worried just run it all the time once its down that low if you keep the cpu constantly loaded its no big deal the temprature fluxuation is minimal. temps like that are no big deal its a problem if you get to coold but it can handle it if done right.

BOWMAN1964
10-07-02, 12:08 PM
let me be the first to say too cold it sometimes not too good.look at my signture.xp2100@2150 -44 loaded.well i lost my l2 because of the cold.if i let the pc boot before the evap temp get below -30 i can run with full L2 CACHE.
butttttt..........................if i let the evap go down to -57 or -60 before i start the pc...I LOSE L2 CACHE.THIS IS A FACT on my setup.I am one of a handfull of guys who can actually run that cold 24/7.so take it from me.IT YOU WANT SUPER COLD TEMPS BE PREPAIRED TO LOSE THE L2 CACHE MAYBE.ALOT DEPENDS ON THE BOARD TOO.AND AT THOSE TEMPS YOU WILL LIKE ME HAVE TO DEAL WITH THE BOARD FREEZING UP TO 8" IN A CIRCLE
AROUND THE CPU.MINE DID AND I HADE TO SUPER INSULATE THE BOARD.
I know alot of people think they know about extreeme cold and refridgeration of computers.BUT I ACTUALLY HAVE ONE RUNNING.not on paper but in the real world.
so just becarefull what you wish for.extreeme cold temps are nice but they have to be handled a little differant.

Jirnsum
10-07-02, 03:10 PM
Just a note on cold temps using the Prometeia. You will see temps of -40, -50, but this is in the evaporator, not on the CPU. The CPU doesn't really get colder than -10 (all in Celsius).

johnnyw
10-11-02, 02:21 PM
hmmm, I think there is a better solution for this.
You should use ( for example in case of cooling you wblock with a freon unit), use a fish tank which would be divided in two.
So, when you want to turn off the computer, first you turn off every program that stresses the cpu and turn off the compressor. At the same time you comunicate the fishtank/reservoir that had in the other (water which was not being used ) cold water but not as cold as the one as the freon cooled one. So you keep on running the pump nad thatīll do the trick.
If you havenīt understood how to make it lol. the fact is that this works.

Penguin4x4
10-11-02, 04:14 PM
Originally posted by BOWMAN1964
AND AT THOSE TEMPS YOU WILL LIKE ME HAVE TO DEAL WITH THE BOARD FREEZING UP TO 8" IN A CIRCLE AROUND THE CPU.MINE DID AND I HADE TO SUPER INSULATE THE BOARD.


Is that explained in the Project X Thread?

Jstic
10-14-02, 10:18 AM
Anyone who thinks that expansion and contraction don't start to affect the CPU until temps below -30 are not being realistic. Anything below freezing will affect your CPU unless you leave it on 24/7/365.

SoNgOkO
10-15-02, 01:19 PM
Only 1 more question!!

What if i turn off the computer and leave the compressor on does that harm the CPU????


Thanx

brodo
10-16-02, 12:56 AM
well I am super new to the water cooling/extreme cooling game, but I think the answer (from reading the replies) is obvious that you would do more damage that way.

having your cpu not emmitting any heat and running the compressor would/could freeze it completely (I think I read that somewhere in another thread) -correct me if I am wrong.

and if that does not happen, what probably will happen is your compressor would drop below your -30/-40 and your cpu would start up too cold and contract the most.

am I correct in my deciphering?<asking the ones that know>

Turando
10-16-02, 02:59 PM
i only plan on running my below 0 setup at about -5 on die. i dont think u would accomplish that much at having it below that.

Cheers, Turando