Two chipmakers are riding the same wave of AI infrastructure spending, yet the market prices them in starkly different ways. Micron Technology trades at forward price-to-earnings multiples of roughly 6 to 13 times, while Broadcom commands around 18 to 30 times. Forward price-to-earnings ratios price a stock against its expected earnings over the coming year, so the gap means investors are paying less for each dollar of Micron's anticipated profit. That gap sits at the center of a question The Motley Fool recently put to investors: which of these two semiconductor names is the better AI buy over the next three years?

Both companies have posted some of the stee growth rates in the semiconductor industry over the past year, but their business models—and the certainty the market assigns to their future earnings—set them apart.

The case for Micron: memory is the bottleneck

Micron leads in high-bandwidth memory, or HBM, along with the DRAM and SSD storage that fill data centers. HBM is the high-speed memory stacked directly beside AI processors, feeding them data fast enough for training and running large models, while DRAM and SSDs supply the working memory and storage behind those systems.

The company reported fiscal Q4 2026 revenue of $54.2 billion, a 379% jump from the same quarter a year earlier. Full-year fiscal 2026 revenue came in at $133.2 billion, up 256%.

Micron guided for fiscal Q1 2027 revenue of $61.5 billion, give or take $1.5 billion, and expects sequential revenue growth throughout fiscal 2027. The company also raised its long-term supply commitments to $32 billion.

According to the research findings on the company, tight supply conditions in memory are expected to persist through 2028. Analyst consensus on Micron stands at Strong Buy, with potential price target upside of about 60% based on late-September figures.

The case for Broadcom: customers who aren't going anywhere

Broadcom builds custom chips and solutions tailored to specific technology giants—in practice, application-specific chips, or ASICs, engineered to each customer's own architecture rather than sold off the shelf. Its customer roster includes Google, Meta, OpenAI, and Anthropic.

The company reported AI semiconductor revenue of $16.7 billion for fiscal Q3 2026, up 221% year over year. It has projected AI semiconductor revenue of about $115 billion for fiscal 2027 and about $230 billion for fiscal 2028. Broadcom also carries a Strong Buy consensus rating from analysts.

Why the valuation gap exists

Micron's low multiple reflects investor concern that today's HBM shortage will eventually ease. Memory has historically been one of the most cyclical corners of the semiconductor industry, with pricing swinging between shortage and oversupply as capacity and demand fall out of balance—a pattern that helps explain why investors discount memory stocks even amid rapid growth. If tightness really does hold through 2028, that skepticism could prove too cautious. Broadcom's higher multiple reflects custom chips built for specific customers that are harder to swap out, while multi-year partnerships with hyperscalers offer visibility that spot memory pricing cannot.

What this means for investors

Broadcom's fiscal 2028 target of about $230 billion leaves little margin for disappointment, and stocks trading at higher multiples tend to react sharply when growth slows. Micron's guidance range of plus or minus $1.5 billion for its next quarter is a reminder that even strong forecasts come with uncertainty.

The key checkpoints are quarterly earnings. Watch whether Micron delivers the sequential growth it has promised through fiscal 2027, and whether its long-term commitments keep climbing past $32 billion. On the Broadcom side, the signal to track is progress toward the roughly $115 billion fiscal 2027 AI revenue target.

Micron offers the cheaper ticket, with more sensitivity to the memory cycle. Broadcom offers predictability—at a price that already assumes things go very well.