They most likely applied a textured (perhaps microscopic) graphene coating to increase the surface area.
If they didn't increase the surface area with the graphene the only way i can see them possibly improving the heat transfer from the metal heat sink to the air is by coating the metal to prevent oxidation.
It seems that coating graphene change some surface properties of metal and thus improve heat transfer. The high heat conductivity of graphene layer itself is not a major contributing factor.
Exactly my thoughts. Simply adding another layer oaf somethng doesn't improve the cooling-abilities at all, as the part with the least conductivity is still the bottleneck of the whole design. Microstexture like seen on sinks with a lotuseffect coating would make hte most sense to increase surface-area.
That Also would increase dust collecting abilities of the surface... so if there Are any benefits, those will dissappear very quicly, but matte black looks good ;)
"Simply adding another layer oaf somethng doesn't improve the cooling-abilities at all" Not true. They've been doing this with aluminum finned copper-core heatsinks for quite a few years. First heatsinks where just aluminum, but it didn't conduct heat as well. Then they tried all copper, which was better but heavier. Then some company created a computer heatsink with a copper-core that had aluminum or aluminum coated fins because aluminum thermally interfaces with air better than copper, but copper has lower heat resistance. Best of both worlds.
This used to be common knowledge in the computer geek community.
pretty sure it was copper core and aluminum fins for production cost and weight reasons. that was the time i build computers and i remember the all copper cooler still had a better standing and higher price. with talk about the cost difference in the material.
""Simply adding another layer oaf somethng doesn't improve the cooling-abilities at all" Not true. They've been doing this with aluminum finned copper-core heatsinks for quite a few years. First heatsinks where just aluminum, but it didn't conduct heat as well."
Your example is NOT ADDING a layer on top, it is replacing part of the material (Al) with another material.
They may as well have said it was coated in pixie dust and unicorn pee because the implication that their use of what amounts to graphene as paint as an improvement is just as much of a deluded fantasy.
In a CPU cooler heat release by radiation is insignificant compared to direct contact with air. For example, the fins will radiate the heat right into the fins next to them, so even fins do not make sense for heat release by radiation. Besides, black also accepts external radiation better.
This cooler is the best performance cooler for its size. This is meant to be used in small form factor cases with low clearance. When you don't know what you're talking about, don't.
Optimum Tech has compared the C7 cu with the C7G and there is no difference in thermal performance. However, the C7G won't oxidize while the C7 cu will with time thus the C7 cu will lose performance while the C7G won't.
Expect to pay extra for this in NAMER as Cryorig has apparently abandoned North American marketplaces. 3rd party sellers on Amazon are currently charging $135 for the basic C7 (I bought one in 2017 for $30), which is a nice markup even on an import.
This has already been tested by NotFromConcentrate; the graphene coating does nothing to improve the performance of the heatsink.
From what I remember of the video the science behind theory is sound but the application of the graphene is not done properly and in the level of precision that would aid in improving thermal performance.
Stick with Noctua if you want the best performing low profile heatsink.
Ummm.... why would you want just the surface fo the heat sink to be graphene? It is indeed a great thermal conductor but the surface of a material is responsible for actually radiating out the heat with air. Wouldn't it be wiser to select a material that is better suited for that application? Graphene would be great for the core material of a heat sink though.
Because grapheme by definition is a surface material. Carbon molecules in a bulk would be graphite or coal, neither one having a particularly high thermal conductivity. Or diamond, which would work very well, but even with polycrystalline artificial diamonds, that would produce the most expensive cooling component of all times, somewhere beyond 10000$ for even a small form factor cooler.
But yeah, graphene coating the copper definitely won't reduce the blocks overall thermal conductivity, it will only increase it by a very, very small fraction. Or at least it can't reduce the conductivity from CPU to Air overall, in theory it might help a bit to equalize the temperature profile on the fin surface in case the air cools it unevenly.
Because graphene is a "2-D" ("2-D" is employed as a figure of speech to mean "extremely thin", not in a mathematically rigorous sense, because that can only exist in pure math) material. It can only be applied as a coating of one to a few, maybe up to a few tens, graphene layers. The 3-D version of graphene is graphite and that will certainly not do because graphite's properties are markedly different.
My black body radiation physics knowledge is currently a bit of rusty at the moment; is a surface with a higher thermal conductivity better or worse at thermal radiation? My guess is that it's better : a near perfect black body with a high thermal conductivity surely absorbs heat better than a black body with a low thermal conductivity. Better heat absorbers are also better heat radiators. Hence, assuming the graphene layer was applied correctly, it should increase the heat radiation from the radiator's fins (and, conversely, in a hot environment that is warmer than the radiator, the graphene should increase the heat absorption).
"My black body radiation physics knowledge is currently a bit of rusty at the moment; is a surface with a higher thermal conductivity better or worse at thermal radiation?"
Radiation has almost nothing to do with how air coolers work.
Would the black colour have an impact on better heat radiation? I seem to remember something about colour impacting thermal properties from school physics classes although I have not idea about the quanta (best guess would be only a degree or two anyone else have a better idea?)
Sure, but since the fins can only radiate towards the fin next to it, which is also black and absorbs all the radiated heat again, that gives you no net effect => 0°C. A radiating cooler needs to be oriented towards something very cold, like deep space when you use it on satellites. There the difference is massive, a polished metal surfaces has a emissivity of less than 10%, while a black coated surface can have an emissivity of very close to 100% => Radiating more than 10x the power.
Nope. The transfer of heat to air does not happen by radiation, it happens by direct transfer (or convection).
Technically very very little is transferred by radiation to water vapor in the air and very very very very very very little to a few molecules of CO2 in air would also happen if the air would be about -100C (as CO2 absorption line is at 15 micrometers, so CO2 misses almost all radiation at normal room temperatures, just a tiny narrow line well off the BBR peak). But both of those are absolutely insignificant compared to convective transfer, and the air radiates the heat right back.
You seem to recall black body radiation. A body with a deep black color is better at absorbing heat (beside visible light) when it is cooler than its environment. Conversely, when the environment is cooler than the black body object, the heat flow reverses : the object gets better at radiating heat to its environment. It also helps when that object, or at least its surface, has a very high thermal conductivity, because that should enhance the heat absorption/radiation.
That radiator does not have a very deep black color though. It seems to reflect at least 5% of the visible light that hits it. The closest you get to an ideal black body (at least for visible light, near and mid infrared) the more you amplify the heat radiation/absorption. A team of researchers coated a large natural diamond with a "forest" of vertical nanotubes that literally turned it into a black void, making it absorb 99.96% (or 99.995%, the article mentions both numbers) of all light that hits its surface, from every angle. Vertical nanotubes form *much* deeper black bodies than graphene because they trap light and heat among them kind of like light is trapped by trees of a very dense forest, though nanotubes are far denser. On the contrary, graphene's layers are horizontal, not vertical, so light is largely trapped among the graphene layers which is much less efficient.
If this was actually graphene, i.e. single layer graphite, it would not look black, as a single layer graphene is invisible to the naked eye. The HB pencil joke earlier is probably a good idea of what the coating is - a carbon paste (perhaps containing graphene or more realistically graphite) on the surface.
Or the protective black paint you have to apply on top of the graphene, because a unprotected graphene layer would probably not survive for very long ...
Or a protective coating to cover up the delusional fantasy designed to land more sales to suckers at a higher price than said suckers were willing to pay previously.
Yeah. What is the point of adding something with potentially better thermal conductivity than copper into a coating that will not have better thermal conductivity than copper.
I thought the graphene meme had died, but it has found a new niche.
It is probably still undefined -at least in the commercial sector, surely researchers have defined it (or not?)- where graphene ends and where graphite starts. A "few layers" of graphene is still considered graphene, but where exactly does it start being graphite? 10 layers? 20 layers? 40 layers? More? Do the graphene layers need to be deposited on one another in a special way, perhaps with intermediate insulating layers of some other material, or not? Do they need to be aligned in a particular way or do they self-align?
For as long as there are no clear answers to such questions (I mean available to the general public, not confined in academic circles), ideally some kind of standard or certification which certifies what graphene is and what is not, most "graphene" sold commercially will be crude graphite.
you mean (the late great) Kurt Cobain?... (song as in “smells like teenage spirit, which was (as rumour/wikipedia goes) the perfume of the drummer of “bikini kill” )... i digress.
I'd like to see a review. If they say it can cool 125w, then I believe them, but I don't see how a coating alone will improve cooling. There must be more to it.
A graphene-coated insulated cooler won't change anything.
I had very high hopes for this company, I truly did, sadly they another company who lost touch with the "how should be being done"
sorry, but how many company we truly need that offer a slight thinner slight higher than "ok" performance IN THE REAL WORLD for in the $90+ range.....
screw that IMO....maybe try ensuring your product are not listed far far far higher than MSRP suggest should be on shelf....like H7 list for under $45, but more oft than not (when could find) was priced ABOVE far far higher performance product...their answer "we cannot control third party price listing"
sure you can, one call to lawyer and a CEASE DESIST given...ahh well, they must make lots of $$$ to be the same as A $%$ other companies doing lately, last one they released was H7 RGB one (from what recall) was WORSE performance but HIGHER price (far more complaint of NOT mount proper) ...I guess their answer was "oh they want CU based coolers that are even higher priced and a shorter cooler that is priced as high if not higher than liquid that trashes anything we are able to list for $60 or less...ahh well, lst us take $2 cooler and charge $90+
LOL...
that is what I see from Logitech, Razer, these folks, Corsair, Cooler "baster" rinse an old product, slap even higher price on....
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Sweetbabyjays - Thursday, September 26, 2019 - link
They most likely applied a textured (perhaps microscopic) graphene coating to increase the surface area.If they didn't increase the surface area with the graphene the only way i can see them possibly improving the heat transfer from the metal heat sink to the air is by coating the metal to prevent oxidation.
wilsonkf - Thursday, September 26, 2019 - link
It seems that coating graphene change some surface properties of metal and thus improve heat transfer. The high heat conductivity of graphene layer itself is not a major contributing factor.Sttm - Thursday, September 26, 2019 - link
Very cool. I want to see a U12A from Noctua coated in it.jrs77 - Thursday, September 26, 2019 - link
Exactly my thoughts. Simply adding another layer oaf somethng doesn't improve the cooling-abilities at all, as the part with the least conductivity is still the bottleneck of the whole design.Microstexture like seen on sinks with a lotuseffect coating would make hte most sense to increase surface-area.
haukionkannel - Friday, September 27, 2019 - link
That Also would increase dust collecting abilities of the surface... so if there Are any benefits, those will dissappear very quicly, but matte black looks good ;)bcronce - Sunday, September 29, 2019 - link
"Simply adding another layer oaf somethng doesn't improve the cooling-abilities at all"Not true. They've been doing this with aluminum finned copper-core heatsinks for quite a few years. First heatsinks where just aluminum, but it didn't conduct heat as well. Then they tried all copper, which was better but heavier. Then some company created a computer heatsink with a copper-core that had aluminum or aluminum coated fins because aluminum thermally interfaces with air better than copper, but copper has lower heat resistance. Best of both worlds.
This used to be common knowledge in the computer geek community.
Lochtror - Tuesday, October 1, 2019 - link
pretty sure it was copper core and aluminum fins for production cost and weight reasons. that was the time i build computers and i remember the all copper cooler still had a better standing and higher price. with talk about the cost difference in the material.peevee - Tuesday, October 1, 2019 - link
""Simply adding another layer oaf somethng doesn't improve the cooling-abilities at all"Not true. They've been doing this with aluminum finned copper-core heatsinks for quite a few years. First heatsinks where just aluminum, but it didn't conduct heat as well."
Your example is NOT ADDING a layer on top, it is replacing part of the material (Al) with another material.
deil - Friday, September 27, 2019 - link
Am I right that they managed to make it ~40% better? if so, it means top gaming laptops will soar.PeachNCream - Friday, September 27, 2019 - link
They may as well have said it was coated in pixie dust and unicorn pee because the implication that their use of what amounts to graphene as paint as an improvement is just as much of a deluded fantasy.peevee - Tuesday, October 1, 2019 - link
Gaming kiddies did not learn physics.Slash3 - Thursday, October 3, 2019 - link
PhysX™Kilnk - Sunday, November 10, 2019 - link
This is too thick for laptops. This is meant to be used in small form factor cases such as the Dan Case.Jorgp2 - Friday, September 27, 2019 - link
A black coated surface will release heat better than a shiny metal one.That doesn't change the fact that this cooler is shit though, they're just rehashing it to save tooling on releasing an actual new product.
peevee - Tuesday, October 1, 2019 - link
In a CPU cooler heat release by radiation is insignificant compared to direct contact with air. For example, the fins will radiate the heat right into the fins next to them, so even fins do not make sense for heat release by radiation.Besides, black also accepts external radiation better.
Kilnk - Sunday, November 10, 2019 - link
This cooler is the best performance cooler for its size. This is meant to be used in small form factor cases with low clearance. When you don't know what you're talking about, don't.Kilnk - Sunday, November 10, 2019 - link
I will add that this cooler can comfortably cool a stock 3900x. It's far from being shit.Kilnk - Sunday, November 10, 2019 - link
Optimum Tech has compared the C7 cu with the C7G and there is no difference in thermal performance. However, the C7G won't oxidize while the C7 cu will with time thus the C7 cu will lose performance while the C7G won't.jtd871 - Thursday, September 26, 2019 - link
Expect to pay extra for this in NAMER as Cryorig has apparently abandoned North American marketplaces. 3rd party sellers on Amazon are currently charging $135 for the basic C7 (I bought one in 2017 for $30), which is a nice markup even on an import.Operandi - Thursday, September 26, 2019 - link
This has already been tested by NotFromConcentrate; the graphene coating does nothing to improve the performance of the heatsink.From what I remember of the video the science behind theory is sound but the application of the graphene is not done properly and in the level of precision that would aid in improving thermal performance.
Stick with Noctua if you want the best performing low profile heatsink.
keyserr - Thursday, September 26, 2019 - link
I use a HB pencil on all my heatsinks.Hul8 - Thursday, September 26, 2019 - link
That's graphite.boozed - Thursday, September 26, 2019 - link
That's the jokeLord of the Bored - Friday, September 27, 2019 - link
Ironically, peeling sticky tape off graphite is a valid production method for small quantities of graphene, so he's halfway there!There's truth in jest, or so they say.
Operandi - Friday, September 27, 2019 - link
I think thats how they actually discovered it if I'm not mistaken.kulareddy - Friday, September 27, 2019 - link
Crayons would work better imo.mikato - Friday, September 27, 2019 - link
I use a graphene crayon on mine.Kilnk - Sunday, November 10, 2019 - link
Noctua performs worse than the C7 cu/C7G lmao what are you even talking about?boozed - Thursday, September 26, 2019 - link
I prefer my heatsinks to be soaked in good old fashioned snake oilGreenReaper - Wednesday, October 2, 2019 - link
This comment wins, right here.Kevin G - Thursday, September 26, 2019 - link
Ummm.... why would you want just the surface fo the heat sink to be graphene? It is indeed a great thermal conductor but the surface of a material is responsible for actually radiating out the heat with air. Wouldn't it be wiser to select a material that is better suited for that application? Graphene would be great for the core material of a heat sink though.ShieTar - Friday, September 27, 2019 - link
Because grapheme by definition is a surface material. Carbon molecules in a bulk would be graphite or coal, neither one having a particularly high thermal conductivity. Or diamond, which would work very well, but even with polycrystalline artificial diamonds, that would produce the most expensive cooling component of all times, somewhere beyond 10000$ for even a small form factor cooler.But yeah, graphene coating the copper definitely won't reduce the blocks overall thermal conductivity, it will only increase it by a very, very small fraction. Or at least it can't reduce the conductivity from CPU to Air overall, in theory it might help a bit to equalize the temperature profile on the fin surface in case the air cools it unevenly.
mikato - Friday, September 27, 2019 - link
If that is the case, it seems nonsensical to compare the thermal conductivity to copper or aluminum.Santoval - Friday, September 27, 2019 - link
Because graphene is a "2-D" ("2-D" is employed as a figure of speech to mean "extremely thin", not in a mathematically rigorous sense, because that can only exist in pure math) material. It can only be applied as a coating of one to a few, maybe up to a few tens, graphene layers. The 3-D version of graphene is graphite and that will certainly not do because graphite's properties are markedly different.My black body radiation physics knowledge is currently a bit of rusty at the moment; is a surface with a higher thermal conductivity better or worse at thermal radiation? My guess is that it's better : a near perfect black body with a high thermal conductivity surely absorbs heat better than a black body with a low thermal conductivity.
Better heat absorbers are also better heat radiators. Hence, assuming the graphene layer was applied correctly, it should increase the heat radiation from the radiator's fins (and, conversely, in a hot environment that is warmer than the radiator, the graphene should increase the heat absorption).
bcronce - Sunday, September 29, 2019 - link
Actually, graphene follows the electric resistance of a mathematical 2d universe.peevee - Tuesday, October 1, 2019 - link
"My black body radiation physics knowledge is currently a bit of rusty at the moment; is a surface with a higher thermal conductivity better or worse at thermal radiation?"Radiation has almost nothing to do with how air coolers work.
shabby - Thursday, September 26, 2019 - link
Can't wait for graphene coated rgb's!Jon Tseng - Friday, September 27, 2019 - link
Would the black colour have an impact on better heat radiation? I seem to remember something about colour impacting thermal properties from school physics classes although I have not idea about the quanta (best guess would be only a degree or two anyone else have a better idea?)ShieTar - Friday, September 27, 2019 - link
Sure, but since the fins can only radiate towards the fin next to it, which is also black and absorbs all the radiated heat again, that gives you no net effect => 0°C.A radiating cooler needs to be oriented towards something very cold, like deep space when you use it on satellites. There the difference is massive, a polished metal surfaces has a emissivity of less than 10%, while a black coated surface can have an emissivity of very close to 100% => Radiating more than 10x the power.
Jorgp2 - Friday, September 27, 2019 - link
Isn't the idea to release the heat from the radiator?As in transfer it into the air.
A surface painted black will do a better job than a shiny metal surface.
peevee - Tuesday, October 1, 2019 - link
Nope. The transfer of heat to air does not happen by radiation, it happens by direct transfer (or convection).Technically very very little is transferred by radiation to water vapor in the air and very very very very very very little to a few molecules of CO2 in air would also happen if the air would be about -100C (as CO2 absorption line is at 15 micrometers, so CO2 misses almost all radiation at normal room temperatures, just a tiny narrow line well off the BBR peak). But both of those are absolutely insignificant compared to convective transfer, and the air radiates the heat right back.
Santoval - Friday, September 27, 2019 - link
You seem to recall black body radiation. A body with a deep black color is better at absorbing heat (beside visible light) when it is cooler than its environment. Conversely, when the environment is cooler than the black body object, the heat flow reverses : the object gets better at radiating heat to its environment. It also helps when that object, or at least its surface, has a very high thermal conductivity, because that should enhance the heat absorption/radiation.That radiator does not have a very deep black color though. It seems to reflect at least 5% of the visible light that hits it. The closest you get to an ideal black body (at least for visible light, near and mid infrared) the more you amplify the heat radiation/absorption. A team of researchers coated a large natural diamond with a "forest" of vertical nanotubes that literally turned it into a black void, making it absorb 99.96% (or 99.995%, the article mentions both numbers) of all light that hits its surface, from every angle.
Vertical nanotubes form *much* deeper black bodies than graphene because they trap light and heat among them kind of like light is trapped by trees of a very dense forest, though nanotubes are far denser. On the contrary, graphene's layers are horizontal, not vertical, so light is largely trapped among the graphene layers which is much less efficient.
Even on my poor contrast TN monitor that "black diamond" looked like it opened a hole in it. Someone with an IPS or OLED screen will surely view this magnificent black in all its glory :
The article : https://phys.org/news/2019-09-blackest-black-mater...
And the diamond picture (before and after) directly :
https://scx2.b-cdn.net/gfx/news/hires/2019/2-miten...
katsetus - Friday, September 27, 2019 - link
If this was actually graphene, i.e. single layer graphite, it would not look black, as a single layer graphene is invisible to the naked eye.The HB pencil joke earlier is probably a good idea of what the coating is - a carbon paste (perhaps containing graphene or more realistically graphite) on the surface.
ShieTar - Friday, September 27, 2019 - link
Or the protective black paint you have to apply on top of the graphene, because a unprotected graphene layer would probably not survive for very long ...PeachNCream - Friday, September 27, 2019 - link
Or a protective coating to cover up the delusional fantasy designed to land more sales to suckers at a higher price than said suckers were willing to pay previously.katsetus - Friday, September 27, 2019 - link
Yeah. What is the point of adding something with potentially better thermal conductivity than copper into a coating that will not have better thermal conductivity than copper.I thought the graphene meme had died, but it has found a new niche.
Santoval - Friday, September 27, 2019 - link
It is probably still undefined -at least in the commercial sector, surely researchers have defined it (or not?)- where graphene ends and where graphite starts. A "few layers" of graphene is still considered graphene, but where exactly does it start being graphite? 10 layers? 20 layers? 40 layers? More? Do the graphene layers need to be deposited on one another in a special way, perhaps with intermediate insulating layers of some other material, or not? Do they need to be aligned in a particular way or do they self-align?For as long as there are no clear answers to such questions (I mean available to the general public, not confined in academic circles), ideally some kind of standard or certification which certifies what graphene is and what is not, most "graphene" sold commercially will be crude graphite.
MASSAMKULABOX - Friday, September 27, 2019 - link
Didnt MiChael Jagger have something to say on this subject ?Smells a bit like Teen Gimmick to me .. but who knows ...
Surfacround - Monday, September 30, 2019 - link
you mean (the late great) Kurt Cobain?... (song as in “smells like teenage spirit, which was (as rumour/wikipedia goes) the perfume of the drummer of “bikini kill” )... i digress.abufrejoval - Friday, September 27, 2019 - link
wonder if pencil dust makes it a dust at-tractor beamJorsher - Friday, September 27, 2019 - link
I'd like to see a review. If they say it can cool 125w, then I believe them, but I don't see how a coating alone will improve cooling. There must be more to it.A graphene-coated insulated cooler won't change anything.
mobutu - Saturday, September 28, 2019 - link
It is already available in stock in europe at roughly 75 eur tax included.Dragonstongue - Saturday, September 28, 2019 - link
I had very high hopes for this company, I truly did, sadly they another company who lost touch with the "how should be being done"sorry, but how many company we truly need that offer a slight thinner slight higher than "ok" performance IN THE REAL WORLD for in the $90+ range.....
screw that IMO....maybe try ensuring your product are not listed far far far higher than MSRP suggest should be on shelf....like H7 list for under $45, but more oft than not (when could find) was priced ABOVE far far higher performance product...their answer "we cannot control third party price listing"
sure you can, one call to lawyer and a CEASE DESIST given...ahh well, they must make lots of $$$ to be the same as A $%$ other companies doing lately, last one they released was H7 RGB one (from what recall) was WORSE performance but HIGHER price (far more complaint of NOT mount proper) ...I guess their answer was "oh they want CU based coolers that are even higher priced and a shorter cooler that is priced as high if not higher than liquid that trashes anything we are able to list for $60 or less...ahh well, lst us take $2 cooler and charge $90+
LOL...
that is what I see from Logitech, Razer, these folks, Corsair, Cooler "baster" rinse an old product, slap even higher price on....
blekk..utter blekk
zodiacfml - Sunday, September 29, 2019 - link
Nope. I saw somewhere that graphene coating adds 1-3% improvementAlways_winter - Monday, September 30, 2019 - link
well for fast cpu's to blossom there needs to be new tech to cool these future heat producing cpuspeevee - Tuesday, October 1, 2019 - link
"To make C7 G's high performance possible, Cryorig had to apply graphene coating on the heatsink."Marketing BS.
peevee - Tuesday, October 1, 2019 - link
Can Anandtech please not to help fraudsters with their obvious frauds? Anton, if you don't understand why this is fraud, ask Ian.