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DIY CPU Thermal Grease, Using Diamond Dust
tygerstripes writes "The dysfunctor has spotted an impressive project over on InventGeek.com; an innovative chap has developed his own thermal compound for improved CPU cooling, using diamond dust — the best available material for thermal conduction — as the key ingredient. In spite of the quick-&-dirty DIY nature of the project, the gains in cooling performance are remarkable, especially considering the material cost was only $33. Given the price many enthusiasts will pay for a top-end cooler, it's easy to imagine this product coming to market quite soon."
...a practical use for your wife's jewelry!
I feel super cool with angel dust, I don't think I'll switch.
I'm god, but it's a bit of a drag really...
not in the incredibly low grade diamonds that aren't used in jewellery. Very small, damaged stones with poor colour (the kind that don't even qualify for the 4 C's) are used in industrial settings - ex. diamond saw blades.
but ain't diamonds the kind of carbon that's supposedly expensive?
Only the kind that are dug out of the ground and sold for the market that's artificially manipulated to keep prices high.
I want peace on earth and goodwill toward man.
We are the United States Government! We don't do that sort of thing.
Large non occluded diamonds are really expensive. The cost then exponentially decreases as size and transparency decrease. As well, small dark diamonds can be manufactured in a lab easily. These two factors lead to diamond dust being extremely cheap compared to its cousins in jewelry.
I'm gonna throw out a spoiler: In a test situation, at full load, the best temperature under Arctic Silver was 57C, while this diamond dust compound achieved 38C. The nearly 20 degree difference is huge, and would definitely make a difference in overclocking. I'm hoping the price can come down when produced in industrial quantities, because it'll be enormously worthwhile.
Ahh yes, my diamond dust. Now where did I put that? I'm pretty sure I keep it with my scrap gold somewhere....
This guy's the limit!
This technology is not new. Diamonds have been used as heat sinks and thermal conductors for processors in sattelites since the 70s (natural diamonds in big sizes, so expensive). Since about 1992 there have been succesful efforts to sinter diamond dust (waste material from the polishing process of gemstones, and now increasingly synthethic diamonds, both are not expensive) for use in thermal conductors.
Nope. Jewellery is nowadays just a little part of the worldwide diamond industry, and while it often uses natural, mined diamonds (mainly because some weird people with bucketloads of cash want to be sure that the diamond they wear is natural and mined, even though it is perfectly possible to produce a diamond of equal aesthetic value in a lab), which are quite expensive, the biggest demand for diamonds is in the tools industry. Most of it goes into production of diamond-tipped cutting tools (which are actually coated in diamond powder or small diamond shards, not made of solid crystal) for the market, the rest is used to make specialized cutting and grinding elements in machines that produce solid carbide tools.
Just check eBay or your local hardware store for the prices of diamond-tipped tools - they're only about twice as expensive as high-quality HSS and often cheaper than good solid carbide cutters, because they're actually just HSS with some diamond powder coating, easy and quick to produce.
This is Slashdot. Common sense is futile. You will be modded down.
Diamond dust in heatsinks? Square-headed girlfriends? To the next level? Now I finally understand why is Shiva's ice attack in Final Fantasy labeled as "Diamond Dust"...
Ezekiel 23:20
Wow, I've been on /. for many years now and haven't gotten one of these trolls directed at me until just now. I wonder if it will show up on my achievements page?
I want peace on earth and goodwill toward man.
We are the United States Government! We don't do that sort of thing.
Look up Gemesis and Apollo. Technology has progressed to the point that we can synthesize diamonds. I don't mean make cubic zirconium, I mean real diamond, made in a lab. It is still expensive in relation to a lot of materials, but it is cheaper than mined diamonds, and getting cheaper.
B&W use it for their tweeters in their high end speakers, as an example.
Are diamonds now a nerd's best friend?
"The tree of liberty must be refreshed from time to time with the blood of patriots and tyrants." ~Thomas Jefferson
That guide was posted a while ago...
Here is a company that sells it premixed and has been around for several years.
http://www.innovationcooling.com/
An idea that was recently (2 days ago) discussed on Hack a Day was using diamond stropping paste
http://hackaday.com/2009/08/03/diamond-thermal-paste/
Here is a reliable review of Diamond thermal paste.
http://hardwarelogic.com/news/137/ARTICLE/2752/2008-03-03.html
As far as just hoping on Ebay and buying your own, good luck. Finding a distributor for your dust and suspension will take you some time.
I think the most important thing people should consider and hasn't been mentioned so far is that the equation for heat transport is linear. Changing the adulterant in the suspension will be more noticeable as the temp increases. IMHO for most people it's a total waste of materials, for some people it's a decent alternative, and for a very small number of people it's a good idea to spend the time locating materials to make a batch.
It really should. That's an achievement worth something! They also need to add a "falling for a goatse troll" achievement - but /. went downhill when they started showing domains after every link.
Socialism: a lie told by totalitarians and believed by fools.
Only because there's no demand for such a product. If there were a market for billions of them, production could be automated at a cheap per-stone cost.
Socialism: a lie told by totalitarians and believed by fools.
Since no one reads the article and seems more interested in whining about diamond prices, here are the improvements that were achieved with the new thermal paste.
Idle - Max load
42c - 57c - Arctic Silver with a fresh application
39c - 54c - Arctic Silver with 2 week cure
29c - 38c - Diamond Grease with a fresh application
These numbers are almost too good to be true. A 19c drop under load with diamond paste? With my 4GHz OC'd system, I'm happy getting 38c when idling. If this data is true, it will really be revolutionary.
Beyond the poor-quality natural stones(which are a modestly abundant byproduct of mining for the good stuff) synthesizing industrial grit size/quality diamonds is now well within the realm of doable. Large/Gem quality ones are either available or in the "real soon now" stage(producers of the natural ones are Not Happy with this...)
Diamond Powder Compound Cost:
100 CTS 60k mesh industrial Diamond Powder: $50
(0.2g : Carat)
36g of Silicon Grease: $20
Final Volume: 56g @ $65 or $1.25/g
Arctic Silver 5: 12g @ $18 or $1.50/g
Key word is "if"
ASCII stupid question, get a stupid ANSI
There are clear shenanigans in play, that or (more likely) methodological errors.
The type of paste you use has very little difference. Let's not forget this comparison which includes toothpaste.
I feel like there is an Arrested Development joke somewhere in here.
Lindsay:
There's a cream with real diamonds in it. I can actually smear diamonds on my face! And it's only $400 a tub! That's, like, what, like, a million diamonds for $400? A million bleeping diamonds!
Diamonds aren't even rare, the only reason they're expensive is because they're produced by cartels that that are more than willing pull underhanded tricks to crush the competition. Granted, really large gem quality diamonds aren't enormously abundant, but the prices on them are definitely inflated.
I read the internet for the articles.
I'm sorry, but the gains he is talking about are simply unrealistic. Lets do a little math shall we?
.75 inches (it will be larger), his CPU is disapating 100 Watts(probably higher than it is), and we take the advertised number for AS5 at 8 W/m*K, and you end up with a thermal circuit that takes 13 degrees to cross.
If we take a rather thick installation of AS5 at 0.015 inches and assume the contact area is a square with sides of
He claims to have a new thermal compound which reduces the temperature by 14 degrees. Now lets take a look at some more realistic numbers... 1 sq in area, 75 watts, 0.010in thick paste, same 8W/m*K and you get a tempeture delta of 4 degrees to cross.
Furthermore, when we start looking at websites that have done reviews of thermal pastes like [url=http://hardwarelogic.com/news/137/ARTICLE/2752/3/2008-03-03.html]IC Diamond 7 Carat[/url] and they show a range of 1-2 degrees difference between AS5 and the paste it makes it hard to belive.
For a little more background, perhaps we should consider what is going on here. We have some material that is being used for thermal conduction, silver or diamonds, and to that we are have a material it is being suspended into. Thermal conductivity of silver is over 400 W/m*K and artic silver which is made from pure silver plus the suspension yields a conductivity of 8 w/m*K. The idea that exchanging that for something with a thermal conductivity of somewhere between 900 and 2000W/m*K is going to yield a paste with orders of magnitude better thermal conductivity.
So based on that, I'd like to call shens. If he made a mistake with his numbers or he faked them I don't know, all I know is the numbers he is reporting are outside the realm of reality.
(producers of the natural ones are Not Happy with this...)
Sellers. Something makes me doubt DeBeers has ever produced a natural diamond.
Or, it could just cost $7.99. I guarantee 1.5 ounces will last you at least a dozen installs, if not more.
Man is the animal that laughs.
And occasionally whores for Karma.
I was going to just mod you up, but I figured your post would soon be at 5 anyway. (if not, mod parent up!)
Yes, you're absolutely right. Lots of bad physics and a completely incorrect conclusion in that article. If there is an improvement in the thermal interface, the heatsink should get HOTTER. All of the heat goes somewhere. That's the first law of thermodynamics... conservation of energy.
You can break it down to a thermal resistance model which is functionally equivalent to an electrical resistance model. Difference in temperature is the "voltage" that drives the flow of heat (current). The heat (current) is a fixed value. The resistances are the various materials the heat has to flow through to get to the air. It can take many parallel and series paths to get out and you can build a resistance network to calculate heat flow through each "path". One way is through the IC leads, into the board, and eventually to the air... or the most direct path is through the heat spreader, through the thermal interface material, into the heatsink and eventually to the air. If the heatsink reads a lower temperature, that means less heat is flowing through the heatsink and that heat is taking a more difficult path to get out and thus the IC junction temperature is HIGHER. That's BAD.
So yes, the math doesn't add up. The thermal interface between the IC and the heatsink should be spread so thin that the thermal resistance across it is almost negligible. Thermal grease is only there generally because it's it's much higher conductivity than air and if you don't have it, all you have is air in all of the little surface imperfections of the heatsink and heat slug on the IC. Adding solid particles to the grease only serves to hold the heatsink and IC heat slug further apart, so even if it's great conductivity, it's generally the wrong thing to do.
-S
--- What parts of "shall make no law", "shall not be infringed", and "shall not be violated" don't you understand?
Not true. It seems that the people who are working on this keep on having "unfortunate accidents."
I wonder if making synthetic diamonds involves placing black cats on broken mirrors under ladders on Friday the 13th?
"-1 Troll" is the apparently the same as "-1 I disagree with you."