Nvidia (NVDA, Financials) has done it; the company just passed Apple’s peak and became the most valuable firm in market history US$3.92 trillion, and counting.

Its chips power the AI boom; its stock powers portfolios. Shares rose another 2.2% Thursday to US$160.60; traders didn’t blink they doubled down.

Nvidia’s climb has been wild; four years ago, it was worth US$500 billion. Today, it’s bigger than all listed companies in the UK; bigger than Canada and Mexico’s markets combined.

And yet it doesn’t feel frothy. The stock trades at 32 forward earnings; well below its five-year average. Profits are soaring; estimates keep rising.

Microsoft (MSFT, FInancials) is next in line at US$3.7 trillion; Apple (AAPL, Financials) trails at US$3.19 trillion. Nvidia started with gaming; now it runs the AI universe.

This article first appeared on GuruFocus.