The two gifts from Moore and his wife, Betty, come with few strings attached and will be used for a list of scientific projects to be developed in the future.
"I'm just so grateful, I don't have words for it," Caltech President David Baltimore said. "It is an amazing gift, really the most wonderful thing that could happen to Caltech."
Baltimore told the Times that the possible projects include designing a powerful astronomy telescope, an observatory to study the movement of the Earth's tectonic plates as well as projects related to chemistry, biology and computer science.
Moore, 72, told the newspaper the gifts -- half in the form of a personal donation and the other over 10 years from a foundation established a year ago by the Moores -- would be used to keep Caltech in the forefront of scientific and technology research, and that we would let the school decide how to spend it.
"I've retained a real interest ... in what goes on in science and technology, and Caltech has been a leading participant in that," he said.
Moore received doctoral degrees in chemistry and physics from Caltech in 1954 and has been on the 2,000-student university's board of trustees for the past 12 years. He had donated about $50 million to the Pasadena school over the past several years.
Moore and partner Robert Noyce launched Intel in 1968 and retired from the Silicon Valley firm last spring.
The gift to Caltech eclipsed the $400 million gift to Stanford University made in May by the William and Flora Hewlett Foundation, and the $360 million given in March to Rensselaer Polytechnic Institute by an anonymous donor.
Microsoft founder Bill Gates gave $1 billion to establish a scholarship fund for minority students, however the gift did not specify a particular school.