In 1982, he co-founded Camintonn with David Sun. in 1986, they sold it for $6 million and founded Kingston Technology. In 1996, they sold 80 percent of the company to SoftBank for $1.5 billion, before buying it back in 1999 for $450 million.
He has supported Erin Gruwell's Freedom Writers and the Freedom Writers Foundation. In 2011, he donated $1.2 million to give every first year medical student at UC Irvine an iPad.