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DIY CPU Thermal Grease, Using Diamond Dust 210

tygerstripes writes "The dysfunctor has spotted an impressive project over on; 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."
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DIY CPU Thermal Grease, Using Diamond Dust

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  • Finally (Score:5, Funny)

    by Anonymous Coward on Wednesday August 05, 2009 @02:50PM (#28961245)

    ...a practical use for your wife's jewelry!

  • *shrug* (Score:5, Funny)

    by i_ate_god ( 899684 ) on Wednesday August 05, 2009 @02:50PM (#28961255)

    I feel super cool with angel dust, I don't think I'll switch.

  • I admit, I don't know jack about jewelry, but ain't diamonds the kind of carbon that's supposedly expensive?

    • by Anonymous Coward on Wednesday August 05, 2009 @02:54PM (#28961313)

      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.

    • Did you even read the Summary?

      especially considering the material cost was only $33.

    • not industrial diamonds, they are about as small as fine sand, you can buy cutting tools with diamond dust embedded in them as reasonable prices
    • by Shakrai ( 717556 ) on Wednesday August 05, 2009 @02:56PM (#28961335) Journal

      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.

    • by Demonantis ( 1340557 ) on Wednesday August 05, 2009 @02:56PM (#28961337)
      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.
      • 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.

        Ah... But is it as much fun to use that dust, as it is pulverizing your wife's diamonds in your mention's basement(a.k.a the secret cave under the house)

    • Re: (Score:2, Insightful)

      by afidel ( 530433 )
      Diamonds are not that rare, DeBeers just has a near monopoly on them. Industrial users won't pay the major markup that suckers will so they sell the non-gem quality ones at a reasonable price.
      • That's what I thought but then I thought to check and apparently* they now only have a 40% share of the market, down from 80%. []

        *According to the Wikipedia

        • by afidel ( 530433 )
          40% is still substantial, and DeBeers probably has enough capital laying around to build their percentage back up by buying and hoarding now when prices are low and then unloading to crash the market thus driving smaller operators out of operations. They've done it in the past, and could likely do it again. Regardless my wife and I have agreed that in the unlikely event we buy another diamond (accent stones are the most likely) it will be a Polar Ice diamond from a Canadian mine not associated with the cart
    • Re: (Score:3, Informative)

      by LotsOfPhil ( 982823 )
      according to the article, about $1/carat.
    • by Enleth ( 947766 ) <> on Wednesday August 05, 2009 @03:06PM (#28961485) Homepage

      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.

      • Re: (Score:3, Informative)

        by afidel ( 530433 )
        It's actually not any cheaper to make an F,FL-IS 1 carat jewel (~2 carat seed stone) then it is to mine it, especially since a lot of the value is in the labor to cut it perfectly.
        • by lgw ( 121541 ) on Wednesday August 05, 2009 @03:26PM (#28961733) Journal

          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.

        • Mod parent up.

          Sure it is "easy" to make diamonds for industrial roles. But it to make one with the size (not to mention color and clarity) for fine jewelry is not.
        • by h4rr4r ( 612664 )

          Why would there by any real labor cost to cut synthetic diamonds? If they all come out the same size and shape automating it should not be very hard.

          • by canajin56 ( 660655 ) on Wednesday August 05, 2009 @03:59PM (#28962191)
            Key word is "if"
            • You can machine-cut diamonds quite excellently, however*.. depending on how much you want to spend on the machine, it'll come out either quite good, or excellent.

              Keep in mind that professional lapidarians also cut using machines.. they don't sit there with a little diamond-gritted tool polishing away for hours on end, holding the diamond between their bare fingers.

              The only 'problems' come from size, shape, and any potential natural faults along which the material may be likely to splice while working it, an

          • by afidel ( 530433 )
            Because even if they have the same outside dimensions the crystalline lattice of each piece will NOT be the same. Gem cutting is more an art than a science.
        • And we all know what upstanding members of their local and international community the companies that run diamond mines and their distributors are.

    • by Sycraft-fu ( 314770 ) on Wednesday August 05, 2009 @03:10PM (#28961527)

      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.

  • bottom line (Score:5, Informative)

    by TheSHAD0W ( 258774 ) on Wednesday August 05, 2009 @02:56PM (#28961343) Homepage

    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.

  • ... diamonds! Like heatskinks, processors, memory ... probably cost prohibitive though.
  • been done before (Score:2, Interesting)

    by Anonymous Coward

    in the do-it-yourself flashlight-making community.


  • by gEvil (beta) ( 945888 ) on Wednesday August 05, 2009 @03:01PM (#28961425)
    Ahh yes, my diamond dust. Now where did I put that? I'm pretty sure I keep it with my scrap gold somewhere....
  • by Anonymous Coward on Wednesday August 05, 2009 @03:04PM (#28961459)

    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.

  • by Totenglocke ( 1291680 ) on Wednesday August 05, 2009 @03:18PM (#28961639)
    Are diamonds now a nerd's best friend?
  • by Anonymous Coward on Wednesday August 05, 2009 @03:18PM (#28961641)

    That guide was posted a while ago...

    Here is a company that sells it premixed and has been around for several years. []

    An idea that was recently (2 days ago) discussed on Hack a Day was using diamond stropping paste []

    Here is a reliable review of Diamond thermal paste. []

    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.

    • People also keep forgetting that they're using passive cooling too so even if they get the most badass water-cooling rig with a dog sized radiator and 12 delta screamer fans they're still not getting below ambient.

  • ...cue up some Jeff Beck

  • $33? You can buy a tube of IC Diamond for only $7. DIY isn't too interesting when it costs so much more than off-the-shelf...

    • It says 7 carat for IC Diamond. Didn't the article mention 28 carats and much higher gain? Or does the 7 carat mean 7 carat after mixing it with the other components?

  • by lalena ( 1221394 ) on Wednesday August 05, 2009 @03:32PM (#28961807) Homepage
    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.
    • Since no one reads the article

      Don't you mean, er, "artical"? I suppose it smacks of me being a spelling nazi, but it makes a site's already too-good-to-be-true claims sound even less valid when the first thing I see on the main page is "Featured Artical", and then realize the same typo is made in equally large text partway down the page.

      It's like when someone insists they're an expert on computers and then says that they bought a Jesus (as in "Hay-Soos") EeePC.

      • by lalena ( 1221394 )
        So you are saying that this plea from the InventGeek site didn't make you want to donate:

        But we alwase can use some help funding new projects for you all. So please donate!

        • So you are saying that this plea from the InventGeek site didn't make you want to donate:

          But we alwase can use some help funding new projects for you all. So please donate!

          Is the new project a good spellchecker? I'll donate to that.:)

    • *mind boggles* This is game changing. 19C reduction is bigger than the difference between a stock intel crappy cooler and a $100 aftermarket tower cooler!

      A lapped heatsink base, match-lapped to the heatspreader took me from 60C to 55C under load. I thought that was a epic reduction for 40 minutes work.

      I wonder how this would work with carefully lapped heatspreader, even bigger reductions?
  • Compared to AS5 (Score:3, Insightful)

    by Krazy Kanuck ( 1612777 ) on Wednesday August 05, 2009 @03:56PM (#28962143)

    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

  • by SporkLand ( 225979 ) on Wednesday August 05, 2009 @04:05PM (#28962265)
    I feel like there is an Arrested Development joke somewhere in here.

    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!
  • While we're on this topic, why don't razor blade manufacturers use diamond dust/shards for the tips of the shaver blades?

    I'm sure some will be thinking 'conspiracy' so joe punter has to buy more, but I'm hoping there's a more rational explanation.

  • by MasseKid ( 1294554 ) on Wednesday August 05, 2009 @04:30PM (#28962613)
    I'm sorry, but the gains he is talking about are simply unrealistic. Lets do a little math shall we?

    If we take a rather thick installation of AS5 at 0.015 inches and assume the contact area is a square with sides of .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.

    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=]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.
    • by sdo1 ( 213835 ) on Wednesday August 05, 2009 @05:08PM (#28963237) Journal

      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.


  • Arctic Silver with a fresh application: System Max load 57c
    Diamond Grease with a fresh application: System Max load 38c

    The author notes that the fancy diamond paste results in LESS heat at the heat sink.

    Conclusion: The home-made paste is more of an insulator than the commercial stuff, as the same amount of heat is being generated, but that heat just isn't making it to the heat sink!

    • by Mashiki ( 184564 )

      If you RTFA, you'd know that onboard and external monitoring was used. Onboard means the embedded temperature sensor in the CPU itself. It doesn't get much more accurate then that, we stopped using external CPU monitoring devices for CPU's 5 or 6 years ago when they started increasing the pin count, and figured "What's one or two more pins, when we're designing against thermal runaway."

  • Check here [].

  • >DIY CPU Thermal Grease, Using Diamond Dust

    I can see it now:

    "Mum, can I borrow your engagement ring?"

Machines that have broken down will work perfectly when the repairman arrives.