"Nintendo 64 is the culmination of work by Nintendo, Silicon Graphics, and MIPS Technologies. The SGI-based system design that ended up in the Nintendo 64 was originally offered to Tom Kalinske, then CEO of Sega of America by James H. Clark, founder of Silicon Graphics. SGI had recently bought out MIPS Technologies and the two companies had worked together to create a low-cost CPU/3D GPU combo that they thought would be ideal for the console market. A Sega of Japan hardware team was sent to evaluate the chip's capabilities and they found some faults which MIPS subsequently solved. However, Sega of Japan ultimately decided against SGI's design, apparently in part due to internal problems between Sega of Japan and Sega of America.
In the early stages of development the Nintendo 64 was referred to by the code name "Project Reality". This monicker came from the speculation within Nintendo that the console could produce CGI on par with then-current supercomputers. When unveiled to the public on November 24, 1995, the console was introduced as the Nintendo Ultra 64 at the 7th Annual Shoshinkai Software Exhibition in Japan." - [wikipedia]