Updates sourcing in paragraph 1, rewrites throughout

By Carlos Méndez and Krystal Hu

Feb 19 (Reuters) - Nvidia NVDA.O is close to finalizing a $30 billion investment in OpenAI, as the chipmaker moves to take a stake in one of its largest customers, a person familiar with the matter said.

The investment is part of a fundraising round in which OpenAI is seeking more than $100 billion, the person said. That would value the ChatGPT maker at about $830 billion and amount to one of the largest private capital raises on record.

SoftBank Group 9984.T and Amazon AMZN.O are also likely to participate in the round, Reuters previously reported.

The investment would highlight increasingly intertwined relationships among major technology companies racing to build advanced AI systems, as chip suppliers, cloud providers and model developers deepen financial and strategic ties.

It would replace a commitment announced in September under which Nvidia would invest up to $100 billion to support OpenAI's use of its chips in data centers, the Financial Times reported on Thursday.

Nvidia declined to comment when contacted by Reuters.

The chipmaker had planned to invest an initial $10 billion once the two sides reached a definitive agreement for OpenAI to purchase Nvidia systems, Reuters reported in September. The agreement ended up taking much longer than both parties expected, the person said on Thursday.

OpenAI is set to use much of the fresh capital to purchase Nvidia's chips, which power the training and deployment of its artificial intelligence models, the person said, declining to be identified as they were not authorized to speak publicly on the matter.

(Reporting by Carlos Méndez in Mexico City and Krystal Hu in San Francisco; Editing by Rashmi Aich and Christopher Cushing)

((Carlos.Mendez@thomsonreuters.com))