Key Takeaways AI stocks had a volatile week as Wall Street reckoned with the implications of a sophisticated, cost-efficient AI model from Chinese start-up DeepSeek.Semiconductor stocks such as Nvidia and Broadcom sold off on Monday as investors worried DeepSeek's efficiencies would temper enthusiasm for AI infrastructure spending.

DeepSeek, a Chinese artificial intelligence (AI) start-up, is sending shock waves through the U.S. tech sector by demonstrating its latest AI assistant, which achieves performance comparable to or even surpassing some of the world's best chatbots.

DeepSeek stunned the tech world with the release of its R1 "reasoning" model, matching or exceeding OpenAI's reasoning model for a fraction of the cost.