For Cai, a trader in Shenzhen’s vast Huaqiangbei electronics hub, the business of assembling computers for gamers and corporate clients has suddenly become dramatically more expensive. The price of memory products in Huaqiangbei has tripled over the past year amid the global artificial intelligence boom – and the spike has hit the world’s largest wholesale electronics market hard. “Right now, memory and SSDs are the biggest cost drivers in a personal computer build,” Cai said, referring to...