NVIDIA. O, one of the hottest U.S. stocks, has surpassed even bitcoin in volatility, fueled by the artificial intelligence craze. The company's shares, which had been surging, were down 7 percent on Tuesday, the biggest drop in more than three months and a loss of $193 billion in market value, buoyed by the industry's spending on NVIDIA chips. The reversal of NVIDIA's 23 percent decline since July 10 highlights a risk that goes unnoticed as NVIDIA's shares rise: It is roughly twice as volatile as Bitcoin by at least one key metric. Despite the stock price's pullback this month, Nvidia is still up about 109% this year, more than any other stock in the S & P 500, with the exception of Super Micro Computer Inc., another company that has benefited from investments in AI application equipment.