The recent AI advances by Chinese upstart DeepSeek could be the beginning of a potential nightmare scenario that Nvidia Corp.

Nvidia's market value dropped more than $500bn after the emergence of DeepSeek - a low-cost chatbot built by a Chinese AI firm.

U.S. equity declines followed a selloff that started in Asia, with Japan's SoftBank Group finishing down 8.3%, and moved through Europe where ASML fell 7% ...