“AI Chips: What They Are and Why They Matter—An AI Chips Reference”, 2020-04 (; backlinks):
Artificial intelligence will play an important role in national and international security in the years to come. As a result, the US government is considering how to control the diffusion of AI-related information and technologies. Because general-purpose AI software, datasets, and algorithms are not effective targets for controls, the attention naturally falls on the computer hardware necessary to implement modern AI systems. The success of modern AI techniques relies on computation on a scale unimaginable even a few years ago. Training a leading AI algorithm can require a month of computing time and cost $100 million. This enormous computational power is delivered by computer chips that not only pack the maximum number of transistors—basic computational devices that can be switched between on (1) and off (0) states—but also are tailor-made to efficiently perform specific calculations required by AI systems. Such leading-edge, specialized “AI chips” are essential for cost-effectively implementing AI at scale; trying to deliver the same AI application using older AI chips or general-purpose chips can cost tens to thousands of times more. The fact that the complex supply chains needed to produce leading-edge AI chips are concentrated in the United States and a small number of allied democracies provides an opportunity for export control policies.
This report presents the above story in detail. It explains how AI chips work, why they have proliferated, and why they matter. It also shows why leading-edge chips are more cost-effective than older generations, and why chips specialized for AI are more cost-effective than general-purpose chips. As part of this story, the report surveys semiconductor industry and AI chip design
trends shaping the evolution of chips in general and AI chips in particular. It also presents a consolidated discussion of technical and economic trends that result in the critical cost-effectiveness tradeoffs for AI applications. In this paper, AI refers to cutting-edge computationally-intensive AI systems, such as deep neural networks. DNNs are responsible for most recent AI breakthroughs, like DeepMind’s AlphaGo, which beat the world champion Go player. As suggested above, we use “AI chips” to refer to certain types of computer chips that attain high efficiency and speed for AI-specific calculations at the expense of low efficiency and speed for other calculations.
This paper focuses on AI chips and why they are essential for the development and deployment of AI at scale. It does not focus on details of the supply chain for such AI chips or the best targets within the supply chain for export controls (CSET has published preliminary results on this topic). Forthcoming CSET reports will analyze the semiconductor supply chain, national competitiveness, the prospects of China’s semiconductor industry for supply chain localization, and policies the United States and its allies can pursue to maintain their advantages in the production of AI chips, recommending how this advantage can be used to ensure beneficial development and adoption of AI technologies.
Key points:
Industry Trends Favor AI Chips over General-Purpose Chips
AI Chip Basics
Why Cutting-Edge AI Chips are Necessary for AI
Implications for National AI Competitiveness
Table of contents:
Introduction and Summary
The Laws of Chip Innovation
Transistor Shrinkage: Moore’s Law
Efficiency and Speed Improvements
Increasing Transistor Density Unlocks Improved Designs for Efficiency and Speed
Transistor Design is Reaching Fundamental Size Limits
The Slowing of Moore’s Law and the Decline of General-Purpose Chips
The Economies of Scale of General-Purpose Chips
Costs are Increasing Faster than the Semiconductor Market
The Semiconductor Industry’s Growth Rate is Unlikely to Increase
Chip Improvements as Moore’s Law Slows
Transistor Improvements Continue, but are Slowing
Improved Transistor Density Enables Specialization
The AI Chip Zoo
AI Chip Types
AI Chip Benchmarks
The Value of State-of-the-Art AI Chips
The Efficiency of State-of-the-Art AI Chips Translates into Cost-Effectiveness
Compute-Intensive AI Algorithms are Bottlenecked by Chip Costs and Speed
U.S. and Chinese AI Chips and Implications for National Competitiveness
Appendix A: Basics of Semiconductors and Chips
Appendix B: How AI Chips Work
Parallel Computing
Low-Precision Computing
Memory Optimization
Domain-Specific Languages
Appendix C: AI Chip Benchmarking Studies
Appendix D: Chip Economics Model
Chip Transistor Density, Design Costs, and Energy Costs
Foundry, Assembly, Test and Packaging Costs
Acknowledgments
See Also:
ChinAI #137: Year 3 of ChinAI: Reflections on the newsworthiness of machine translation
U.S. vs. China Rivalry Boosts Tech—and Tensions: Militarized AI threatens a new arms race
The Node Is Nonsense: There are better ways to measure progress than the old Moore’s law metric
Sustainable AI: Environmental Implications, Challenges and Opportunities