Nvidia races to $2T mark as AI mania sparks Wall Street tech rally

Nvidia galloped to a $2 trillion market value on Thursday after the bellwether for AI chip demand once again exceeded Wall Street's sky-high expectations, re-igniting a global rally in tech stocks. The chipmaker returned as the third most valuable US company as its shares jumped 15%, or more than $100, to a record high of $780.85. If the gains hold, Nvidia will add about $260 billion to its market capitalization. The rally in the top-performing S&P 500 stock also lifted its counterparts in the chip sector, sending the benchmark index, Europe's STOXX 600, and Japan's Nikkei share average to record…