Nvidia reported strong second-quarter earnings with a 56% annual sales increase, surpassing expectations despite a slight miss in data-center revenue. The company revealed that two anonymous customers accounted for nearly 40% of revenue, highlighting significant customer concentration risks. Investors are cautious due to Nvidia's massive $4.44 trillion market capitalization, where further rapid growth is challenged by the law of large numbers. Nvidia also faces geopolitical tensions, limiting sales in China and empowering local competitors like Cambricon.