Here's a puzzle that sounds impossible: Nvidia's stock price has gone up, yet one of the most closely watched gauges of how expensive a stock is — its forward price-to-earnings (P/E) ratio — has actually gone down.

A forward P/E compares a company's share price to what analysts expect it to earn in the year ahead. The number can fall in two ways: the price drops, or expected earnings climb faster than the price. According to Yahoo Finance and The Motley Fool, which published the analysis, Nvidia is a case of the second. The company's projected earnings have grown quickly enough to outpace its rising share price, which mathematically pulls the ratio lower.

As the Yahoo Finance piece puts it, when a company's earnings growth outpaces its recent stock gains, the stock "presents a more compelling valuation for new investors" — while noting that long-term holders haven't been shortchanged, since the shares have still risen. MSN summed it up bluntly: Nvidia is "even cheaper despite outperforming the S&P 500 this year."

GuruFocus framed the same trend as Nvidia's valuation "cooling" even as its growth potential remains intact — a sign that the stock's price is being backed by real, expanding profits rather than pure hype.

Why this matters: Nvidia has been the poster child of the AI boom, and critics keep warning its stock looks bubbly. This quirk cuts the other way — it suggests that, at least by the forward P/E measure, the company's soaring earnings expectations are keeping pace with its share price, a reminder that a rising stock and a richer valuation don't always move together.