Jim Cramer says Big Tech is underspending on AI. Here's why they may need to spend more

1. Big Tech plans to spend $320 billion on AI by 2025. 2. Alphabet exceeded earnings estimates, indicating sound AI investment. 3. Cramer believes AI investments are urgent and critical for tech giants. 4. Nvidia's chips are essential for advancing AI technology. 5. The AI sector's growth is driving overall market gains.