A cash and stock offering for ARM could be announced next week, sources say.
Nvidia is best known for its video game graphics processors, but it has also ventured into other markets, including artificial intelligence, autonomous vehicles and data centers.
ARM provides chip technology for virtually all mobile devices, such as phones and tablets, but they are also entering the market for automotive processors, data center services and other devices.
The British company does not manufacture chips. Instead, it licenses the core technology so others can make chips with it. It has previously collaborated with Nvidia.
Last year, Nvidia said it would make its chips work with ARM processors to build supercomputers, going into systems that are used for climate change and nuclear weapons prediction models.
SoftBank bought ARM for $32 billion in 2016, the largest acquisition in its history, in part to get into the internet of things technology, which connects everyday devices, from traffic lights to refrigerators, to the internet.