Estimation question
Estimate the cost advantage of Groq's LPU vs. NVIDIA H100 for a high-volume workload.
- Groq
- Estimation
- Hard
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What this question tests
Structured cost-comparison estimation across two different hardware architectures for a defined workload.
How to approach it
- Define the workload: assume a high-volume inference task, say serving 1 billion tokens per day for a mid-size language model.
- Estimate H100 throughput and cost: assume an H100 processes roughly 2,000 to 4,000 tokens per second for this model size, at a cloud rental cost of roughly 2 to 4 dollars per GPU-hour.
- Estimate LPU throughput and cost: assume Groq's LPU delivers a meaningfully higher tokens-per-second rate for the same model, say 3 to 5 times higher, due to its architecture, at a comparable or somewhat higher per-chip hourly cost.
- Compute cost per million tokens for each: divide hourly cost by tokens processed per hour, showing the LPU's higher throughput can offset its potentially higher hourly rate, yielding a lower cost per token overall.
- State the conclusion as a range: assume the LPU comes out roughly 30 to 50 percent cheaper per token at high volume, clearly marked as an illustrative estimate, not a verified figure.
What a strong answer includes
- Builds the comparison on cost per token rather than cost per hour, since hourly chip rental price alone is not what a high-volume customer actually pays for.
- States both throughput and hourly cost assumptions explicitly for each chip, showing the tradeoff rather than asserting Groq wins without arithmetic.
- Arrives at a clear range, not a false-precision single number, and labels it explicitly as an estimate based on assumed figures.
- Notes the advantage is workload-dependent, since batch training workloads may favor H100s while low-latency serving favors the LPU.
Common mistakes
- Comparing hourly rental price alone without normalizing for throughput differences between the two architectures.
- Presenting a specific number as if it were a verified fact rather than an assumption-based estimate.
Likely follow-up questions
- How would this comparison change for a training workload instead of inference?
- What would happen to this cost advantage if NVIDIA cut H100 rental prices by half?
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Learn the skill behind it
Chapters of the AI PM course that teach what this question tests.
- Chapter 2: Data fluency: SQL, logs, and reading the truth yourself
- Chapter 9: Prove it paid off: outcomes, economics, and pricing
- Chapter 14: Get the job: the AI PM interview loop