XIAN: Samsung Electronics and Micron Technology, two of the world’s largest reminiscent chipmakers, warned that strict Covid-19 restrictions in the Chinese city of Xian could disrupt their chip production bases in the region. The city blockade puts more pressure on global supply chains and adds to a challenging year for exporters facing particularly high freight costs, even as the costs of raw materials, adding semiconductors, jump amid the two-year pandemic. The restrictions may lead to delays in the source of DRAM memory chips, which are widely used in knowledge centers, Micron said Wednesday. The strict restrictions, which went into effect...