The S&P 500 and the Nasdaq hit over one-week lows on Monday, as the surging popularity of a low-cost Chinese artificial intelligence model knocked shares of chipmaker Nvidia and other companies benefiting from investments into the technology.

Chinese startup DeepSeek has rolled out a free assistant it says uses lower-cost chips and less data, seemingly challenging a widespread bet in financial markets that AI will drive demand along a supply chain from chipmakers to data centers.