The diamond layer that helps an AI chip shed its heat

A server can have powerful fans and still struggle to move heat away from a tiny patch inside a processor. Before heat reaches the air or liquid that carries it out of the machine, it has to travel through the chip, its attachments and its package. Synthetic diamond is being inserted into that journey as a heat spreader.[2]

The technology is already being offered in AI servers. Akash Systems announced an AMD Instinct MI350X system with manufacturer MiTAC in March 2026, describing diamond cooling as an addition to existing air and liquid systems. That distinction is fundamental: the diamond helps heat travel through the package; the rest of the system still has to remove it.[1]

Spread the hot spot

Diamond can conduct heat exceptionally well while remaining electrically insulating. Element Six supplies chemical-vapour-deposited thermal grades with stated conductivities from 1,000 to 2,200 watts per metre-kelvin. The material spreads a concentrated heat source across a larger effective area before the cooler has to carry the heat away.[2][3]

One published Element Six case study, developed with A*STAR’s Institute of Microelectronics, makes that mechanism visible. A silicon test chip contained eight small heaters, each 450 by 300 micrometres. Researchers attached it to a diamond layer 400 micrometres thick, then to a silicon cooler combining microjets and microchannels. Gold-tin solder formed the thermal joints.[3]

At 54 watts of heating power, infrared images showed the maximum temperature falling from 140°C without the diamond layer to 102°C with it—a 38°C difference. This was a deliberately constructed thermal test chip and cooler, not a production GPU running a language model. It demonstrates how strongly package design can affect a hot spot under the tested conditions.[3]

The joins count too

Thermal conductivity belongs to a material. Thermal resistance describes how hard it is for heat to travel through a particular piece of that material and its surroundings. Thickness, area and the interfaces between layers matter. An excellent conductor can still deliver a disappointing result if a poor attachment becomes the main obstruction.

A simplified calculation shows why a headline material improvement does not transfer directly to the whole server. Suppose one layer contributes a quarter of a stack’s thermal resistance. Doubling that layer’s conductivity, while keeping its dimensions and every other resistance unchanged, halves its contribution. Total resistance falls from four illustrative units to three and a half: a 12.5% reduction. This is an explanatory example, not a measurement of either manufacturer’s product.

The material also has to survive manufacture and repeated heating. Element Six offers copper-diamond composites that combine diamond-rich regions with machinable copper regions and copper surfaces for bonding. Its sheet lists bulk conductivity near 800 or 1,000 watts per metre-kelvin at 300 kelvin (about 27°C) for two compositions, and notes that the final result depends on the thickness of the outer copper skins. These composites and a pure CVD diamond layer are different engineering choices.[4]

From a cooler chip to useful computing

MiTAC’s current product page claims up to a 10°C GPU temperature reduction and up to 22% more floating-point operations per watt. These are manufacturer performance claims, with a different scale and purpose from the thermal test-chip experiment. The same page lists fifteen rear-mounted fans: a useful physical reminder that a diamond heat spreader remains part of a cooling system.[5]

A lower chip temperature can create room to sustain performance that would otherwise be restricted by thermal throttling. Akash’s launch material also describes operating at higher ambient temperatures. Which benefit an operator obtains depends on the workload, temperature limits and the surrounding cooling design; the conductivity figure alone cannot establish a site-wide electricity saving.[1]

That makes the purchasing question specific. How much additional useful work does the completed server deliver under the operator’s conditions, and what does the upgrade cost? The most valuable diamond in this setting is a well-integrated component close to the heat source. Its quality is judged by the thermal path it improves.[2][5]

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