To pore over graphics chip maker Nvidia‘s stock chart is to look at a company that has outperformed the market by an order of magnitude. Since its debut on public markets in the late 1990s, shares have rampaged more than 33,000%. The PHLX Semiconductor index advanced about 2,500%.

So it’s no wonder that Nvidia (ticker: NVDA) opted Friday to issue investors three additional shares for every one they own, marking its first stock split in 14 years. Nvidia trades at a pricey 44 times forward earnings, and 74 times last year’s...