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Hardening PCs for Hostile Environments?
labradore asks: "I must install a 1.2GHz Athlon system, in a secure place, at a retail business. The PC is going to be a security video recorder and a point of sale terminal server. In other words I need it to act like an appliance: something that requires very little on-site maintenance and at most, remote adminstration. Unfortunately the only secure place to put it is inside a hot, dusty storage room. It has it's own protective lock-box (approx. 3x3x3 ft.) to keep evil employees and snooping types out and to insulate it from the heat and dust of the storage room but I don't know how to actually keep the box cool and fairly free of dust." What things would one need to house comodity components in such a way to enable them to survive in such hostile environments? Is 27 cubic feet too small for the necessary modifications that would have to be made?
"There must be a lot of other people turning PCs into "embedded" controllers or appliances facing the same situations. At the very least this could be thought of as the quest for the ultimate "fire-and-forget" cooling environment. What options has the collective mind of Slashdot uncovered and thunked up to deal with this kind of situation?"
If you don't need it to be that fast, Underclock the CPU and the motherboard. Test out the minimum configuration necessary to get it working. Then completely seal the 3x3x3 box.
Under-clock the processor, and use filters on the fans pulling air in. This will work for a mildly hostile environment. Perhaps using multiple 120mm fans and washable filters, then you might be able to get away with a room tempurature 90F (32C) degrees. If the tempurature is going to be higher than that and the air dirtier than filters can handle, then you would need to take more extreme measures.
My OEM style PC with an Athlon 1100 is doing fine in my apartment without air conditioning. It has not had any problems with the room tempurature being in the high 80s. At work we had the air-conditioning for the NOC fail for part of a week end, the tempurature was in the low 90s when we got in there. Nothing crashed and we have not seen any problems with any of the dozen Sun servers nor the few Cisco Routers since then. It was not something I would desire to repeat though.
Alumunum is a very good heat conductor. All the better heat conductors cost much much more to use. Look into using a copper CPU heatsink to better transfer heat away from it, but check the overclocker sites to really find out which heatsink is the best bang for the $$$ you are willing to spend.
I'm looking at having to make a PC for outside use in the near term future. I'm going to make it's case out of large area AL heatsinks. I'll be using a heat pipe to transfer the CPU's heat to one side, and use a dual sided heatsink on the other side to cool the rest of the components. Items like hard disks will be directly mounted to the side walls to provide better heat conduction. The idea is I want to make it so it doesn't need fans at all. It needs to run off of solar and batteries only.
There is a company called Blackbox that sells all sorts of lockable cabinets for computer systems. You might want to check out their ClimateCab and ClimateCab Desktop products. I've used these with great success in dirty and hot environments. They are NOT cheap ($4,686.95 and $3,564.95 respectively) but they are the best that I've found that include security, filtration, and cooling.
If "disco" means "I learn" in Latin, does "discothèque" mean "I learn technology"?
Remember, it is your ass on the line when the PC fails because the environment is too harsh for it.
Even if practices like that work for a while, they're still not a good idea. PCs should be kept out of dusty environments, or cleaned regularly (every few months - more or less, depending on how fast dirt builds up) if they must be in one.
If it is truly a dusty environment, and you want to keep the maintainence low, seal the box. You can get Peltier junction A/C units- not very efficient or quiet (because of the fans), but they do have the advantage of allowing a sealed box. This one will remove 550 BTU/hr. You don't need to keep it cold, just remove enough heat so that the computer doesn't fry itself. There will be some leakage of air into it- no big deal, but because of it, you will need some way to get rid of the water that condenses on the cold side of the junction- your periodic maintainence will have to include some sort of dessicant, or at least making sure the drain holes are clear.
I wouldn't overclock the processor, but some OC tricks will be useful...
Consider watercooling this machine. I would have picked a CPU that won't heat your house, but that's irrelevant at this point.
Consider getting a peltier if you've got a beefy powersupply, it's not your electricity!
Seal the case and the enclosure well! I had a box crap otu on me because mice got inside. They pissed all over the motherboard. I got the sucker, found him trapped under the HD enclosure.
Consider setting up a cam pointed right at the enclosure.
Definately get MBM so you can remotely monitor the temperature.
Good luck!
(me: 433@487 Celeryo. CPU temp: 59C. Ambient: 82F)
...Time is the best teacher, unfortunately it kills all of its students.
What's to prevent someone from cutting power to the whoel store (or just the supply room) and doing dastardly deeds? Do you have backup power?
Can anyone unplug the power strip it's plugged into?
What's the case made of? Wood? Sheet metal? Is it a commercial box or something you/someone else fabricated?
3x3x3 should be OK, but if you have problems I would consider some sort of heat exchanger unit.
...Time is the best teacher, unfortunately it kills all of its students.
That way, you can have a couple of beers when you (inevitably) have to fix it. The second bonus is that your beers will be *real* cool if the uptime runs into decades ^_^
-- Cisk for the Cisk God
Overclocker's dot com
they can, will, and in some states must help you
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Put it in a steel box, with a Fan with a filter on the top for Posative pressure, and lock it down.
If an employee wants it that bad, they will find a way.
You can get a cheap safe for about 100$ and cut a 4x4 hole for a Cheap computer fan, and secure it on the top, and bottom. That way, you would first have to get the stuff through a 4x4 fan, an through a spinning fan. Not very easy.
It all depends an how long the user is willing to go without.
You have two problems, dust and heat. Enclosing the unit within a cabinet won't really keep either out. But you CAN solve both problems at the same time. Put the unit into an enclosed cabinet. Have the customer purchase a small chiller with filters, which will probably have to go into a separate (hopefully less dusty) location. Funnel the output from the chiller through some ductwork, and run the other end through a small hole in the cabinet. And presto, you have a positive pressure, cooled environment for your hardware. The cooling takes care of the heat, and the positive pressure keeps the dust out. Hopefully, holes in the cabinet for cables, etc will be enough to keep the pressure regulated, but if not, you can always add some additional small holes. And, BTW, I've seen some chillers that are only about 1 foot deep, 2 feet high and 2 feet wide.
DISCLAIMER: I do not warrant the above information in any way, nor will I accept responsibility if it fails or creates other damage. Use at your own risk!
GreyPoopon
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GreyPoopon
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Why is it I can write insightful comments but can't come up with a clever signature?
Just close the box really tight and use water
cooling for the cooling. I think that could work
for decades on end.
Just an idea.
Oelewapperke
Bolt large heatsinks to both the inside and outside of one side of your lockbox (strip the paint off first). Install a fan inside blowing air over the heatsink. If possible install another fan outside blowing air over the outside heatsink, and if possible replace the steel between the heatsinks with aluminum. This technique is used in some military equipment.
Warning: this article may contain humor, sarcasm, parody, and perhaps even irony. Read at your own risk.
Don't worry about the dust. We have computers in a middle school shop room full of dust and sawdust that have been operating for 3 years with no cleaning and no problems. Don't worry about the heat unless its over 95F consistently. If it is just buy a medium size fan and run it continously. Keep the machine at floor level. We have a hot wiring closet with two servers with hot conditions and everything has been running for over 4 years without a hardware failure.