By Che Pan and Casey Hall BEIJING/SHANGHAI (Reuters) -Demand in China has begun surging for a business that, in theory, shouldn't exist: the repair of advanced Nvidia artificial intelligence chipsets that the U.

Despite U.S. bans, Chinese buyers spent over $1B on smuggled NVIDIA AI chips like the B200, openly sold on Chinese social apps.

Nvidia has only just been allowed to recommence sales of its H20 AI chipset, which has been specifically developed for China to comply with U.S. restrictions.