The value of the US tech company Nvidia has soared by a quarter after it predicted a boom in demand for its computer chips to meet the needs of artificial intelligence products such as ChatGPT. Nvidia's share price rose by 25% in early trading on the back of the announcement, and gave it a market valuation of more than $940bn (£760bn) after stock markets opened on Wall Street on Thursday, up from $755bn on Wednesday evening. The share price had already more than doubled over the course of 2023, amid huge optimism over the rapid progress of generative AI products. These require massive datacentres full of semiconductor chips to operate. The hype was kicked off late last year after the startup OpenAI revealed ChatGPT, a chatbot capable of producing extraordinarily human-like answers to users' queries – albeit with problems around accuracy.