Nvidia's Drop Casts Doubt on AI Boom.

Shares of Nvidia and other major players in the AI industry slipped after a powerful rally, with Nvidia falling 5.7% on Wednesday, the most since January. The AI theme has been a hot topic on Wall Street this year, but lofty valuations are a reason for caution in the still nascent industry. Nvidia's blowout revenue forecast added fuel to the frenzied rally, but cracks appeared in Asia as well, with three Nvidia suppliers cooling after big gains in May. Despite the recent dip, Nvidia is still trading at 23 times estimated sales for the current year, leading some to question if the chipmaker is now too pricey.