Worries about how much money companies are pouring into artificial intelligence are unsettling technology stocks, according to several market reports this week.

Nvidia, the chipmaker whose processors power much of the AI boom, saw its shares fall 1.5% even as rivals AMD and Intel climbed, per Blockonomi. The site noted that investors are increasingly treating Nvidia like a mainstream Big Tech name rather than an untouchable high-flyer, and are watching closely ahead of earnings reports from Microsoft and Amazon this week.

The pressure isn't limited to chipmakers. Yahoo Finance UK reported that Alphabet, Google's parent, has slid from $404 to $318 a share, prompting questions about whether the drop is a buying opportunity. SiliconANGLE framed the mood bluntly, saying AI spending "still spooks investors" as AMD challenges Nvidia and the U.S. pushes back against Chinese AI models.

Some commentators are urging caution on the sector altogether. Memeburn reported that CNBC's Jim Cramer is arguing that "boring" stocks are a better bet than AI names right now.

The unease extends overseas. According to bastillepost.com, an analyst said China's stock markets are experiencing volatility as uncertainty grows around the AI and semiconductor sectors.

The common thread is a growing question among investors: whether the enormous sums being spent on AI infrastructure will pay off, and how soon.

Why it matters: AI-linked giants now make up a large share of major stock indexes, so a shift in sentiment about their spending can ripple through the retirement accounts and investment portfolios of ordinary people, not just Silicon Valley.