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Sub Zero Cooling: a unique approach

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thamaestro

Disabled
Joined
Mar 10, 2002
Location
Colorado, USA
As we know, the component's temperature in a PC is a function of various factors, but it is always added on top of the ambient air temperature. This is why we have the °C/W rating for heatsinks. (ie:
temperature = (c/w(rating)*watts+ambient) etc...)
What if one were to cool the ambient air in the case, as opposed to directly cooling a handful of components?
A brute force option, i know...
This approach would have quite a few advantages:
1. UNIVERSAL COOLING
I want to cool the CPU, GPU, North-bridge, HDD's, etc...
This way, i don't have to have a waterblock for every stinking component. If you've ever done a DIY project, you know the less complicated, the less things could go wrong. (Keep It Simple Stupid)
2. MINIMAL CONDENSATION
Condensation can only occur if the ambient air is colder than the solid surface. There are freakishly few chances that this could occur in this setup: the main one being when the compressor shuts down( but still, -30 degree air can't hold any dangerous amount of water...)
3. SAFETY
The Ambient air has enough 'thermal capacitance' to keep the components alive for quite a while in the case of a catastrophic cooling faliure.
4. STABILITY
The air acts as a temperature buffer between the vapor change components and the CPU... Meaning, no freakishly huge variations between idle temps and workload temps.

I guess the question i can't figure out is: how cold can i get the air?
I'm guessing around -30 °C, but i really don't know.
I figure it's gotta be below freezing point (how else would my freezer get its name?).
This approach has difficulties in the area of insulation... i figure i can cover the inside of my ANTEC file server case with neopreme easily enough... And the case has to be airtight, but not entirely. If I just cover every crack with neopreme or closed cell foam, it shouldn't be a problem...
I plan on using the 80mm fans that came with the case to mount on the hypothetical evaporator coils, to keep the air inside moving around.
The compressor would be inside the case (next to the PSU) and the condenser coils would be hooked up outside through some convieniently cut holes.
WHADDA YA THINK?
If there's some reason this couldn't work, tell me before i spend too much money...
 
similar to what i wanted to do i was gona find a mini fridge and put a big hole in it errr maby 2 then run 2x 120mm dryer exaust hoses with fans on both ends and push freezing air through my comp but i thought i might have to many probs plus my parents would freek at the energy bill grrrr:mad:

but i hope this works for u are u shure u can find a compresser and coils that small?

good luck:cool:
 
If you made a sealed case and filled it with dry nitrogen
you could cool it down as much as you like without fear
of condensation. You would need hermetic seals for all
the external connections.
 
rivercom9 said:
How much do you think a setup like that would cost?

The big cost items would be the hermetic seals. They would
have to be custom made. There are companies that
specialize in this. I looked into it last year and saw that the
dollars were going to fly out of my wallet. :eek:

Now if you were going to start a commercial venture.....
the cost would be reasonable. $400-500 range.
 
I did something similar a while back, well when I say similar I didn't build any cooler device but cut a hole in my floor, (mobile home), and a large hole in base of the PC case to match the floor hole and placed the PC over it.

Lowest the outside temps went that winter was -10C and I had a mobo temp of -4C in a room ambient of 21C at one point. The case was cold to the touch but just below condensation formation point.

Not sure you have got the understanding of the condensation thing right as condensation will form on objects that are colder than the ambient air, related to humidity. This means cold air into a warm PC is fine, its the other way around that is bad. It's just when you turn it off that you could get condensation as the air returns to normal ambient but the PC case and components may stay colder for longer leading to possible condensation issues.

I'm running a ground cooling system now with waterblocks on everything as silence was my goal, with coolant temps at 12C atm. I still get condensation in peak summer ambient when the humidity is high........ real pain in the *** this moisture in the air thing. here's a useful condensation formation point chart that so far I've found to be near as damn it spot on.

//www.zytec.worldonline.co.uk/pictures/gifs/condensationchart.gif

www.zerofanzone.co.uk
 
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You can use a vortex tube to freeze the air. It can output compressed clean air at -40 C, and it only needs an compressed air as input. No moving parts, no energy required. The only problems are the hot air generated, compressor and noise.
 
BladeRunner... Nice chart! I've been looking high & low for something like that.. thanx!
 
rivercom9 said:
Exactly what are hermatic seals?

They are seals that wont pass water or gas. Industrial
ones can usually handle a good pressure differential
as well. They are usually made of special glass or
metal. In the case of a lightly pressurized dry nitrogen
case they could be plastic.

Think of how many cables that come out of your PC. Of course,
the CDROM and such would have to be outside the
seal to be useful. :)
 
The cool thing about BladeRunner's chart is that as a
rule of thumb for NORMAL temps and humidity in your
home is that you don't need to worry about
condensation unless you go colder than 7C below ambient.
 
Hi!!

First I'd like to say:
What a lively forum!! Geez!! People live on the internet!!
I didn't expect a reply for days... and it's only been 4 hours!!

Second, a couple clarifications:
Yes, i understand the condensation rule. That was a mistype.
My bad.:rolleyes:
My tower is big enough to sucessfully mount a refigerant compressor the size of an ATX PSU, if not a couple inches bigger. I can fit a coil the size of a normal (not X-ATX) board in there too.
But i don't think i can fit a condenser, so that'll have to be outside the case.
I live in colorado, the relative humidity here NEVER gets above 45%, so i really don't think there'll be condensation issues.
Thanx for the Nitrogen Suggestion, techumseh, but i think for that kinda cash i'd go get a Kryotech Case... (no offense)
What is a vortex tube 4r4k4w4? That sounds up the alley...
 
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