A growing debate is emerging across the data center and AI-infrastructure world: are operators dramatically overestimating the useful economic life of AI server GPUs? Many analysts now warn that optimistic depreciation models—often based on assumptions that these chips will reliably function for five to seven years—may be setting the entire ecosystem up for a painful correction and leaving investors exposed if performance degrades earlier than expected. For a fuller exploration of this debate, see Aravolta’s recent blog post on GPU depreciation.
Carbice's CTO, Dr. Craig Green's recent article in the Winter 2025 edition of Electronics Cooling cuts directly to the heart of this issue. It highlights the overlooked but fundamental problem of reliability—specifically, how cooling practices and the properties of the thermal interface determine whether GPUs can actually deliver the long-term performance that financial models assume. And at the center of this reliability equation is the component that holds the whole thermal stack together: the thermal interface material. In this article Craig articulates Carbice’s thinking on modern electronics thermal design, especially as it relates to AI chip architecture. It is absolutely worth reading in full, but the key points are:
- Much of contemporary thermal design thinking is dominated by a desire to minimize initial junction temperature, largely due to the implicit relationship between the Arrhenius equation and failure acceleration factors.*
- Failure in modern electronic systems, however, is insufficiently explained with Arrhenius-based analysis and instead requires a detailed understanding of thermomechanical fatigue, thermal gradients, and localized hot spots.
- The Carbice Pad’s combination of extremely high lateral conductivity, conformal compressibility, and cohesive integrity make it uniquely suited to addressing these thermal challenges and distinguish it from other legacy thermal interface materials as an optimum solution for device reliability.
- The high temperature-dependent warpage and dynamic flexures of modern AI chip architectures create an urgent need to rethink thermal design priorities and consider new solutions that can enable the industry to achieve performance and cost goals.
Redefining “High-Quality”
Part of the reason Craig wrote the article is to answer the extremely important question: What is the essential functionality of a high-quality thermal interface material?
As the article articulates, thermomechanical fatigue, thermal gradients, and localized hot spots are just as important, if not more important, than junction temperature when designing for the stable and reliable functionality of electronic devices. Carbice has seen this time and time again as too much emphasis is placed on a single metric when choosing a thermal interface material, the easily measured initial junction temperature, while a TIM’s effect on thermomechanical fatigue, thermal gradients, and hot spots, as well as its long-term stability, is de-emphasized. Given this over-emphasis on initial junction temperature, it is not surprising that companies with access to real data center GPU thermal history, such as Aravolta, are observing unaccounted for maintenance and thermal stress as the selected TIMs weren’t designed for the uniquely taxing interface dynamics associated with AI chips and their real-world operation over time. These observations help validate Carbice’s belief that when TIM selection is overly influenced by the desire to minimize initial junction temperature, long term device thermal management, and therefore device performance, will suffer.
Thermomechanical fatigue, thermal gradients, and localized hot spots are just as important, if not more important, than junction temperature when designing for the stable and reliable functionality of electronic devices.
At Carbice we believe high-quality thermal interface materials required by modern data centers exhibit the following essential functionality in order to increase the useful economic life of hardware and IT equipment and improve ROI on their investments:
- Sufficiently low thermal resistance so as not to exceed chip heat tolerance specifications and therefore induce chip throttling or damage.
- Extreme stability over the lifetime of the chip such that thermal resistance does not increase due to shear delamination, compression set, dry out, void formation, or other existing TIM failure modes.
- The ability to efficiently spread heat in three dimensions to effectively eliminate lateral thermal gradients and hot spots.
- Ease of installation and re-work to minimize total cost of ownership.
- Robustness to transport, long shelf life, and a secure supply chain to simplify logistics.
A Solution Designed for Reliable Performance Over Time:
We believe that Carbice Pad is uniquely positioned to provide the performance and reliability that the high CapEx investments associated with AI data centers need to maintain their performance well beyond commissioning. We believe this because Carbice Pad was explicitly designed to exhibit all this essential functionality:
- Carbice Pad’s combination of thermally conductive and elastic nanotubes allows for the efficient transfer of heat as well as intimate conformal contact that results in thermal resistance values of < 0.1 °C cm2/W.
- Carbice Pad’s elastic nanotubes are also capable of absorbing large amounts of stress and therefore eliminate both shear delamination and compression set so that thermal resistance does NOT increase over time (and in fact in many instances it slightly decreases over time).
- Carbice Pad’s vertically aligned nanotubes have a thermal conductivity of 12 °C/W and aluminum core has a thermal conductivity of 200 °C/W, giving the Carbice Pad excellent thermal conductivity both through-plane and in-plane, therefore helping to minimize thermal gradients and hot spots.
- Carbice Pad is applied with a simple peel-and-stick methodology that allows for both easy assembly and re-work, helping to minimize labor costs and downtime.
- Carbice Pad is unaffected by the vibrations and mechanical shocks associated with transport, is shelf stable at ambient temperature for years, and is made at commercial scale in the United States from simple commodity feedstocks.
Carbice Pad’s unique ability to absorb thermomechanical stress, reduce hotspots and thermal gradients, and maintain performance after hundreds of thousands of power cycles without degradation makes it the clear choice for Data Center applications.
Learn more about the science of Carbice.
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