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CPU Cooling with 15 Liters of Water
ninjagin writes "While not an OC-er, I do enjoy reading about the lengths people will go to on their way to a better CPU cooling solution. I ran across this very interesting article at overclockers.com about this guy's immense 15-liter water cooling rig for his home office PC. Might be just the kind of thing to have the contractors include when they pour your next garage slab."
i can keep my cpu temp down 10 degrees celsius by leaving the door to the backyard open. it's not 15 litres of water, but it keeps it cool. i mean, no need to get crazy :x
Well, plumbing copper shouldn't corrode to easily. Using distilled water should prolong the possibility also
Ah, did you read the referenced article?
:-)
Basically, his hear exchanger was the annode in an unintentional battery
The copper corrodes a little, as copper in water or air always will. This is not normally a big deal, because a thin copper oxide layer forms and protects the rest of the metal. But in the process, some copper ions go into solution and make their way around, thanks to the pump, to the aluminium water block. They precipitate onto the water block surface as teeny little metallic copper particles.
And then plain old galvanic corrosion can happen, as the copper and aluminium are in physical, and thus electrical, contact, and both immersed in the electrolyte. The dreck you end up with is mainly aluminium oxide, with its greenish colour donated by a light lacing of copper oxide. Tah-dah.
When I flame-tested some of the precipitate, by the way, this was borne out; green flame from the copper, bright sparks from the aluminium. Case closed.
Incidentally, when I was trying to track down information on this subject, I discovered that if you start searching for "galvanic corrosion" in the company of some other computer-cooling-relevant words, you're likely to find a large number of pages belonging to homebrew enthusiasts, and a smaller number of pages belonging to nuclear reactor technicians.
Neither of these groups of people want galvanic corrosion to happen in their equipment, but judging by the degree of unhappiness expressed by those who have had equipment destroyed by it, it would appear to be much more irritating when it ruins a batch of beer than when it results in radioactive liquid sodium spraying all over a control room.
I'm not Seth.
Using a copper waterblock instead of aluminum helps prevent this, as does using some sort of additive to inhibit the corrosion (water wetter or a little anitfreeze).
'I ain't a liar, baby, and I ain't proud I just want what I'm not allowed.' -- Violent Femmes, 36-24-36
If you're not overclocking why even bother?
Noise. I watercooled my PC for about a year, and then dismantled the system and replaced it with a heatsink+fan so I could rework/overhaul it. The PC is at least twice as loud as it was before. For some people, that level of noise is unacceptable.
'I ain't a liar, baby, and I ain't proud I just want what I'm not allowed.' -- Violent Femmes, 36-24-36
Oh I perfectly well understand the desire to reduce noise from a PC. My current PC has a cheap case fan and power supply and can charatibly be escribed as a jetplane. It rather annoys me.
However, as you allude to, his solution is not necessiarly the best nor the most ecenomical. For myself, I have ordered a new power supply and case fan. Total cost is about $110 with shipping. Now provided the information on these units is accurate, it should cut the fan noise to a level such that the vibrational noise of the harddrives becomes a bigger concern.
This is generally a much more cost effective solution and also a more practical one, as you don't tie your computer to one location. Just locate good, quite fans from a company like Papst. Then, find a powersupply that has been made for silence. A number of companies take powersupplies from companies like Sparkle and upgrade them with better fans and more efficient electronics to give better sonic results. You can also find some powersupplies that are totally silent, they operate only with a large heatsink, no fan at all.
All in all, if you took a fanless VGA cooler like the Zalman ZM80A (rated for GEForce 4 class cards), a silent powersupply, a quiet CPU cooler and one quiet case fan it would be easy to have a high performacne system with fan noise under 20dB at 1 metre. At that point your harddrives would be a hard larger problem, which water cooling does not help.
Freezers are made to keep cold things cold, or to bring things down from room temperature to freezing. They CANNOT deal with a continuous heat load in the 200W range, at least not for long (burned out compressor, anyone?).
Leaks are actually very rare.
-WolfWithoutAClause
"Gravity is only a theory, not a fact!"So he lowered the noise of his machine be nixing the CPU fan. He still has the powersupply fan to deal with. We have servers at work (1U rack mount) that are p4 2.0ghz machines whose only cpu cooling is a copper HSF combo and they really arent that loud. There are 12 of them and honestly the loudest part of the boxes are the powersupply fans. Even with those on and under heavy load (cluster used for wireless simulations), its still really quiet. He could have saved the cash and bought quiet fans and a new powersupply.
Ive also had positive experiences with the latest Dell boxes. P4 2.0ghz machines that you can barely tell are on because they are so quiet. If they can be that quiet, any machine can be built with that kind of noise output.
I do applaud the effort, but I wonder about his practicality.
Liquid sodium is pretty good too, and a "eutectic" alloy of sodium and potassium melts at much lower temperatures.
Then, instead of a boring neurotoxin like mercury, a leak could cause an unextinguishable class D fire with smoke full of sodium and potassium hydroxide (think Drano(tm), or oven cleaner).
1986 Suzuki GSX-R series race motorcycles used oil as the cooling device - oil ran through the radiator on the front of the bike to cool it off.
Oil can get hotter than water at regular pressures withouth boiling, can be sprayed directly onto the hotspots (which often benefit from the lubrication of the oil also) and does not have the corrosion problems of water.
So yes, there are systems that use oil to transfer heat the way water does. If I am not mistaken oil doesn't conduct electricity the way ionized water does, but it would still make a fscking mess if it leaked inside the computer case.
Glonoinha the MebiByte Slayer
Most cars use less than 15L of coolant and run a lot hotter (Aprox 208F) ... you would think that a more efficient system could be developed.