AMD did not break out a specific revenue number or forecast for its AI chips, a move that is bothering investors.

By Kanchana Chakravarty and Zaheer Kachwala (Reuters) -Advanced Micro Devices shares tumbled 8% on Wednesday after the company's AI chip revenue failed to meet analysts' high expectations, underscoring its struggle to grab market share from well-entrenched market leader Nvidia.

Nvidia was gaining early on Wednesday after Google-parent Alphabet committed to spending on artificial-intelligence infrastructure and rival Advanced Micro Devices’ AI chip revenue disappointed. Nvidia shares were up 0.