BEIJING

Lenovo Group Ltd’s Yang Yuanqing asked for patience as he tries to get China’s top PC maker growing once more, but for the first time publicly vowed to step down as chairman and chief executive if he doesn’t deliver on a critical sales goal.

Yang, who helped grow Lenovo into the world’s largest PC maker but also orchestrated the acquisitions of Motorola and IBM’s low-end server business, is now betting big on artificial intelligence. He wants to plough $1 billion over the next three to four years into research, joining a race with much larger rivals Alibaba Group Holding Ltd. and Tencent Holdings Ltd. to crank out the next generation of intelligent, user-aware devices. Nearer term, he intends to transform the company’s sales online into an e-commerce juggernaut that can bring in 80 billion yuan ($12 billion) of annual revenue within three years.