Nvidia, the Californian tech company known for its PC GPUs, has seen a surge in market value, briefly overtaking Apple as the world's most valuable company. And the reason isn't video games. It's AI.

On Friday last week Nvidia's stock market value reached $3.53tn, overtaking Apple's $3.52tn, as reported by Reuters based on LSEG data.

At the end of that day, Apple remained on top at $3.52tn, but at $3.47tn Nvidia saw an overall market value increase of 0.

8 percent. LSEG data shows Nvidia, Apple and Microsoft are in a three horse race as the world's most valuable companies. Nvidia briefly hit the top spot back in June, but was overtaken by both Microsoft and Apple shortly after.

By comparison on Friday, Microsoft's market value was $3.18 trillion. The reason for Nvidia's increased market value is it's become the dominant supplier of processors used in AI computing, which requires huge amounts of processing power.

Additionally, earlier this month, Nvidia unveiled a new AI model that reportedly outperforms the likes of Chat GPT maker OpenAI (thanks VentureBeat ). It marks a shift for the company as it enhances its AI capabilities alongside its typical GPU offering. "More companies are now embracing artificial intelligence in their everyday tasks and demand remains strong for Nvidia chips," Russ Mould, investment director at AJ Bell, told Reuters.

"It is certainly in a sweet spot and so long as we avoid a big economic downturn in the United States, there is a feeling that companie.