Nvidia is set to report its quarterly earnings after the closing bell Wednesday with investors fretting about lofty AI valuations.

Wall Street shares have seen big swings this week as investors brace for all-important earnings from AI bellwether

Not as expensive as it used to be, based on one widely watched valuation measure—the price-earnings ratio. While Nvidia's stock price has soared, its earnings power has risen even quicker, pushing down the PE ratio.

Viewed through that lens, Nvidia looks compelling. But there are real risks.

Nvidia was again the heaviest weight on the market, and its drop of 3.2% brought its loss for the month so far to 10.8%. That's a steep enough fall that Wall Street has a name for it: a correction. What Nvidia does matters disproportionately to investors because it's the most influential stock on Wall Street.

The U.S. stock market is swinging through another jarring day on Tuesday, following a sell-off that swept Asia and Europe, as worries about too-high prices keep dogging Nvidia, bitcoin and other Wall Street stars.

Asian shares have fallen in cautious trading after worries about Nvidia and the overall market frenzy over artificial intelligence technology sent Wall Street stocks lower