The superstar run for Nvidia’s stock the last few years has been astonishing. So was its tumble Monday, which caused $595 billion in wealth to vanish.

Wall Street has perceived the company to have an almost unbreachable defense against competition with its offerings of high-tech chips. The company’s rapid growth and windfall profit have helped push other technology firms and the Nasdaq Composite Index to record after record,

Nvidia Corp., the poster child of the AI frenzy, sank 17 per cent and headed toward the biggest market-cap loss for a single stock in market history. The AI leader wiped of $500 billion of its market value and shed 21 per cent off its stock price in two days.

Nvidia and other U.S. tech stocks are holding steadier Tuesday, a day after tumbling on doubts about whether the artificial-intelligence frenzy really needs all the dollars being poured into it. The S&P 500 was 0.