DeepSeek, a Chinese AI startup, is making waves, and not just in the AI space -- it's shaking up the US stock market too. Nvidia, the undisputed king of AI chips, saw its stock lose about $600 billion in market value on Monday, as investors started worrying about what DeepSeek's success means for Big Tech's spending spree. So, what's going on?

DeepSeek's sudden rise has reignited an ongoing debate: Is AI investment out of control? US tech giants have been throwing billions into AI infrastructure, and Nvidia has been riding that wave. But if companies start rethinking their spending, that could mean trouble for Nvidia, whose business depends on AI firms buying its chips in bulk.

DeepSeek's success suggests China might not need Nvidia as much as everyone thought. And Chinese companies are either building their own chips (like Huawei's Ascend processors) or optimising AI models to run on less powerful hardware. That could mean fewer sales for Nvidia, and investors don't like the sound of that.

Is it time to cash out?

Let's be real -- Nvidia's stock has skyrocketed over the past year, thanks to the AI boom. But when a stock soars that high, it doesn't take much for investors to start cashing out. DeepSeek's success might have been the excuse some investors needed to lock in their profits before the AI hype train slows down.

Nvidia's slide isn't just about one company -- it's a sign that investors are rethinking AI spending, competition, and valuations. The AI gold rush is still going strong, but there are some serious questions about how sustainable it all is.

Wait, why are nuclear power stocks falling too?

Nuclear power stocks, which had been seen as big winners in the AI revolution, also took a beating. Shares of Constellation Energy and Vistra dropped more than 20 percent, even though AI data centres are expected to need a ton of electricity. So, what's going on?

Nuclear power providers are seen as essential to powering AI data centres. A big part of the nuclear power hype came from the idea that AI would drive a massive surge in electricity demand. That's still likely to happen -- but maybe not as fast as investors had hoped. If AI companies slow down their spending on infrastructure, power providers might not see the huge demand spike they were counting on right away.

Just like with Nvidia, some investors saw an opportunity to cash out. Nuclear stocks had already jumped on the AI boom, so with AI stocks slipping, it made sense for some investors to take their winnings and move on.

So, what's next?

DeepSeek's rise is shaking up the AI world, and investors are adjusting their bets. Nvidia and other AI stocks are feeling the heat, while nuclear power stocks are taking collateral damage. The AI boom isn't over, but investors are being a little more cautious -- and that means more volatility ahead.

The big question now: Is this just a bump in the road or the start of a major AI market reset?