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Is Your Silver-based Thermal Paste Really Silver?
strider69666 writes "Over at Overclockers.com they have a review of several thermal compounds that claim to have 99% pure silver content. 'I decided to test Arctic Silver 5, Arctic Silver 3, OCZ Ultra II Premium Silver Compound, and CompUSA Silver Thermal Grease. This test was not conducted to test performance, but rather to determine if these compounds have Silver as an ingredient.' Using a professionally mixed testing solution, they found that several brands do not, in fact, contain any silver at all! So, are you getting what you are paying for?"
http://www.ocztechnology.com/displaypage.php?name= recall
From the above site:
OCZ would like to take this time to address the recent article published at Overclockers.com, ( http://www.overclockers.com/articles938/ )which shows that OCZ Ultra 2 thermal compound has no silver content.
OCZ does not manufacture Ultra 2 thermal compound in house, it is provided by a foreign manufacturer with our specifications. Previous independent lab tests conducted at the request of OCZ have shown that the silver compound content in Ultra 2 is 25% by volume and 70% by weight.
In response to this article, OCZ has submitted another batch of Ultra 2 to a third party for extensive lab testing. This Independent lab report show's that the most recent batch of OCZ Ultra 2 indeed contains less than 1% silver by volume. While simultaneously we have received lab reports from an outside source indicating the silver content to be 30% by weight. This leads us to the conclusion that recent batch(s) of OCZ Ultra 2 from our supplier did not meet the agreed specifications.
We accept full responsibility for these problems and we will be seeking legal action against our supplier.
In order to help solve this problem we have contacted Arctic Silver Inc, and entered into a vendor agreement with them to supply OCZ thermal paste.
Beginning January 22nd 2004 we are issuing a full recall of any and all OCZ Ultra 2.
Any Customers who wish to return OCZ Ultra 2 thermal paste with an invoice will in exchange for their full or partially used tube(s) receive:
1- One (dependant on # of tubes returned) 3-gram OCZ thermal Compound (made by Arctic Silver Inc.) or one OCZ Dominator 2 Heatsink.
2- One OCZ EL DDR T-Shirt
3- One 10 dollar off rebate on any OCZ EL DDR Dual Channel Kit (at participating resellers)
Comp USA brand silver thermal grease is, indeed, marketed as having silver content. Not just silver coloring, but, explicitly, silver content. Take a look at this before they take it down: compusa.com Product Listing.
In addition, the author claims that similar claims were made on the label of OCZ paste. Judging by the reaction from the people at OCZ (or the people that claim to be OCZ) and his accuracy in the rest of the test, I have no reason to doubt him.
Please, think before you spout the tired, cynical rhetoric about shady advertisement.
Silver is better conductor than copper, and certainly a better conductor than aluminum!
e xt/Ag/key.html
"Pure silver has the highest electrical and thermal conductivity of all metals, and possesses the lowest contact resistance"
From http://www.webelements.com/webelements/elements/t
Actually, silver is a better thermal conductor than copper or aluminum. IIRC, it goes:
(In Watts per meter per degree Kelvin)
Silver ~420 W/mK
Pure Copper ~400 W/mK)
Pure Aluminum ~240 W/mK)
If you REALLY wanted some fancy shit, try a diamond paste. Diamond is like 2000+ W/mK. Really good at transfering heat. (No, I don't know if anyone actually makes the stuff).
Oh, and just for reference, air is about 0.025 w/mK, and water is somewhere around 0.6ish.
So you could use a copper paste, but it wouldn't be quite as good as the Silver.
"no acutally gold has the highest electrical and thermal conductivity of all metals. that is why it is used in microchips"
Please, someone tell me what is the point of blabbing misinformaton about things of which you are utterly ignorant?
Silver has far higher thermal conductivity than gold.
Gold, 320 W/m/K
Silver 430 W/m/K
To the extent gold is used in microchips, it is for other reasons.
As other have mentioned, this is wrong. Silver is the best conductor, followed by copper, then gold. (see http://hypertextbook.com/physics/electricity/resis tance/ for more details)
What gold does do best is resist corrosion, which is why it is often used for connectors. Silver and copper both oxidize very rapidly, causing bad connections, but gold does not.
It may have just been a coincidence, but I think they may be just forbidding links from Slashdot. I opened it in a new tab and reloaded it so I wouldn't have the Slashdot referrer and it worked instantly.
Heat sink goop is a terrible conductor of heat. It is actually a very good insulator of heat.
Here is a measure of the heat conductivity of some stuff (watts/in. degree C)
air - 0.00076
nylon - 0.00635
heat sink goop - 0.0168
brick - 0.0175
glass - 0.02
silver heat sink goop - 0.0282
alumina - 0.7
steel - 1.7
silicon - 2.5
brass - 3.05
aluminum - 5.5
gold - 7.4
copper - 10.0
silver - 10.6
diamond - 16.0
Note that any heat sink goop is a terrible conductor of heat. The only thing it is better than basically is air. Thus, heat sink goop is only to be used to fill microscopic voids between the heat sink and the CPU. If you actually have a layer of it between the heatsink and the CPU it will insulate the chip a LOT and make it overheat.
Thus, there is no reason to use a lot of heatsink goop, it isn't critical that you use good goop. It is VERY CRITICAL that you have good enough heatsink pressure that your heatsink and CPU come in direct contact, with as much as possible heat sink goop squeezed out. There shouldn't even be a visible film of it after heat sink removal, just small pockets in the imperfections on the chip.
Oh, all these figures are stolen from "Hot Air Rises and Heat Sinks: Everything You Know About Cooling Electronics is Wrong" by Tony Kordyban. The book, BTW is just okay. I don't really recommend it to the average person.
"Silver is the best conductor ... Gold is the next best conductor, AFAIK, and doesn't tarnish."
No, actually silver is #1, copper is #2, and gold is #3.
Silver 430 W/m/K
Copper 400 W/m/K
Gold 320 W/m/K
Aluminum 235 W/m/K
Didja know that those silver candy balls used on cupcakes have real silver? Check the label next time you see a container of them. They don't seem to be legal anymore in CA, TX, CO, NJ, AZ, and FL. Darn, and so tasty!
HIV Crosses Species Barrier... into Muppets
IRC, copper conducts heat better than silver...
Last time I checked, that isn't the case. Silver has the best thermal conductivity of all elemental metals (at least all common ones - I don't actually have an extensive list in front of me). Slightly, but not drastically, better than that of copper. And with respect to other to other responses to the parent, the conductivity of aluminum, while better than, say, steel, pales in comparison to that of copper or silver.
See FrostyTech, or Tom's Hardware if you don't believe me.
The use of aluminum is a consequence of price and of system requirements. You can cool a Pentium II, for instance, adequately with an aluminum heatsink because it doesn't put out as much heat. Modern processors, on the other hand, put out more watts of energy which needs to be rapidly sucked away from the cpu and dissipated, so a heatsink with a copper core at the very least tends to be the norm.
Why don't we see more silver heatsinks? Price, of course. Copper is already relatively expensive, but a big block of high purity silver is out of the price range of most people. At that point water cooling probably has a better price performance ratio.
The angel in the oatmeal.
In the UK we also have the Small Claims Court, but the case here might be against teh small corner shop who sold you the stuff, and they might defend the case....
No system of legislation is perfect, but it seems to me that fraudulent claims like this should automatically be actioned by the authorities everywhere, with no need for private individuals to have to pay for lawyers.
In any case, if you have been ripped off, first politely request a refund and compensation, and if they refuse, report them to whatever official body deals with such things locally. They will soon get the message.
BTW I have no sympathy whatsoever for any overclocker who has had a meltdown. Overclocking is a very unsound practice, for a number of reasons, which I have aired on /. before and will not bother repeating. It DEFINITELY shortens the life of your equipment, that is provable fact. But, I don't condone fraud, and no silver look-alike is likely to have adequate thermal conductivity.
BTW, copper is almost as good as silver, you would never be able to detect the difference in practice, in fact it might be better because it could be used in higher concentration, and being slightly softer in pure form, the individual particles might deform better to give more contact area. Other metals such as gold or platinum are absolutely useless, despite any spurious claims that may be made. Any testbook on material properties, with tables of thermal conductivity, will show why.
Which is exactly why you want [the thermal transfer compound] to contain silver, silver is one of the best conducters of heat there is.
Have you checked out Dan's Data on thermal greases? He does a very nice comparison between Artic Silver 3, Cooler Master PTK-001 and HTK-001, Nanotherm "Ice" and "Blue", and... Toothpaste and Vegimite. While Dan may be quite mad, even for an Aussie, there is definitely method to his madness. After measuring the effects on cooling with his usual methods... the difference amounts to diddly-squat. And yes, that includes the difference between Artic Silver 3 and Toothpaste. (Actually, toothpaste was marginally superior.)
So, yeah, there may not be much point to getting too upset if you've gotten thus screwed-- it probably won't make jack-all difference in your system.
On the other hand, it is definitely immoral and almost certainly illegal to claiming "99.9% silver content" when you mean "99.9% silver free". While it was probably a harmless scam (and probably saved this disreputable company some chump change in manufacturing their overpriced goop), whatever Three-Letter-Agency has jurisdiction should probably come down on these folk like a ton of old hard drives on the principle of the matter.
//Information does not want to be free; it wants to breed.