S&P 500, Nasdaq reach all-time closing highs on AI dealmaking boost

By Stephen Culp NEW YORK (Reuters) -The S&P 500 and the Nasdaq advanced on Monday, as artificial intelligence-related dealmaking boosted investor sentiment even as the U.S. government shutdown extended through its sixth day. The Nasdaq and the S&P 500 reached record closing highs, while the blue-chip Dow inched lower. Chips took the lead after AMD said it would supply AI chips to OpenAI in a deal that could generate tens of billions of dollars in yearly revenue and would allow the ChatGPT creator to buy a stake of up to 10% in the chipmaker. AMD surged 23.7%, while the broader Philadelphia Semiconductor Index rose 2.9%. "The market is seeing some strength in areas like technology and consumer discretionary and it's flying in the face of the government shutdown," said Robert Pavlik, senior