Investors are sending two leaders of the AI trade in opposite directions.

Alphabet GOOGL 1.53%increase; green up pointing triangle took another step toward $4 trillion in market value on Tuesday, rising more than 1% to extend a monthslong rally fueled by enthusiasm for the Google parent’s AI tools, cloud computing and chip business. Nvidia NVDA -2.59%decrease; red down pointing triangle shares slid 2.6%, dragging the world’s biggest company by market capitalization further below a $5 trillion valuation reached just weeks ago.