Speaker 1: It was one of the worst days for tech stocks in years, caused by a Chinese AI assistant almost no one has heard of. DeepSeek topped Apple's App Store in both China and the US after the company said it took just two months to build its chatbot using second-generation NVIDIA chips.

Speaker 2: And what's impressive is they did it with just six million dollars, which is a fraction of what the US tech companies have spent to build such capable AI models.

Speaker 1: It prompted investors to rethink the worth of companies like NVIDIA, which makes the computer chips AI companies rely on.

Speaker 3: There's now been a reassessment of the US and NVIDIA's leadership or even necessity in this AI boom.

Speaker 1: NVIDIA shares plunged, losing almost one trillion dollars in market value, a record drop.

Speaker 2: They happened to be selling the shovels, the GPUs that were powering this AI revolution. People discovered that perhaps you didn't need quite as many shovels as you thought you did.

Speaker 1: The drama kept coming with DeepSeek saying it was hit by a cyber attack and US President Donald Trump weighing in with a warning for American companies.

Speaker 4: The release of DeepSeek AI from a Chinese company should be a wake-up call for our industries that we need to be laser-focused on competing to win.

Speaker 1: Last week, the president announced $500 billion joint venture Stargate to fund American AI and counter China's advancements. The mass sell-off of US tech stocks didn't wash all the way through the Aussie share market. The ASX 200 closed marginally lower. The biggest drags were on data-centred developers like Goodman Group and uranium miners as investors realised the AI revolution wouldn't be as energy-hungry as first thought.

Speaker 3: Whether you're an investor directly in the stock market or indirectly through your superannuation, you are going to be impacted.

Speaker 1: As the AI race gathers pace. Rachel Clayton, ABC News.