Chinese tech stocks posted a near four-year high on Thursday as AI-fuelled buying and a regulatory ban on an Nvidia Corp. chip boosted prospects for domestic rivals. The Hang Seng Tech Index rose as much as 2% on Thursday, before fading into the close, building on Wednesday’s 4.2% rally that marked its highest close since November 2021. Gains followed a Chinese regulator’s order to halt imports for Nvidia’s RTX Pro 6000D, seen as a boost for domestic chipmakers. Chinese chipmaker SMIC contributed the most to the tech index’s advance, with shares surging as much as 8.3% in Hong Kong. Hua Hong Semiconductor Ltd. jumped as much as 13%. Shares of Alibaba Group Holding Ltd. and Baidu Inc., which are developing their homegrown alternatives to foreign chips, also rose.