Nvidia is reportedly weighing an eye-popping $250 billion financing guarantee to help OpenAI secure one of the largest AI infrastructure projects ever planned, a move that would cement the chip giant's dominance at the center of the artificial intelligence boom.According to The Wall Street Journal, Nvidia is in talks to back financing that would allow OpenAI to lease a massive 10-gigawatt data center being developed in southern Ohio by an energy subsidiary of SoftBank.The proposed guarantee would cover the data center lease and related debt financing. It would not include the cost of Nvidia's AI chips, though the Journal reported the company is also exploring separate financing for OpenAI's chip purchases that could be worth as much as $350 billion.Nvidia and ChatGPT logos are seen in this illustration taken, September 22, 2025 (Reuters)The sprawling Ohio project is expected to cost more than $500 billion overall, including the advanced chips needed to power the facility, making it one of the most expensive AI infrastructure projects ever proposed.For OpenAI, the deal would represent a major step toward building its own AI infrastructure and reducing its dependence on cloud providers such as Microsoft, Amazon and Oracle. For Nvidia, it would help lock in years of demand for its industry-leading AI processors.U.S. Commerce Secretary Howard Lutnick is reportedly involved in determining access to this critical resource (Getty)The Journal reported Nvidia's backing is designed to reassure lenders by supporting the financing vehicles behind the project rather than directly paying for construction.The first phase is expected to come online in 2028, generating about 800 megawatts of computing power. According to the report, electricity for the site would come from a U.S.-controlled power allocation backed by separate Japanese funding tied to a recent trade agreement and Tokyo's pledge to invest $33 billion in a natural gas plant.Seven in 10 Americans oppose building data centers for AI near their homes, according to a Gallup poll conducted in March (Getty Images)The report also said U.S. Commerce Secretary Howard Lutnick has been involved in deciding access to that power supply. While OpenAI is reportedly the leading contender for the project, Anthropic, Microsoft and Google have also held discussions with Lutnick in recent weeks.The reported negotiations underscore the staggering sums now flowing into artificial intelligence as technology companies race to build the computing power needed for next-generation AI systems. Industry spending on AI infrastructure is expected to top $700 billion this year.