Chinese military bodies, state-run AI research institutes, and universities have been buying banned Nvidia semiconductors from unknown Chinese suppliers.

Despite US export restrictions, these purchases show the difficulty in cutting off China's access to crucial US chips for AI and sophisticated computers.

The chips include the A100 and H100 models that were banned in September 2022, showing the continued demand and the lack of alternatives for Chinese firms.

The suppliers do not include Nvidia or approved retailers, suggesting an underground market for these chips in China.

US authorities plan to tighten loopholes in export restrictions, aiming to impede China's AI development.