Microsoft Chairman Bill Gates on Friday started out a busy day in the Bay Area by talking to college students about a range of topics, from open-source software to malaria to the next Xbox.

In a chat with engineering students at the University of California at Berkeley, Gates said there is much work that needs to be done if the PC is to fulfill its promise. While maintaining that the "glass is half full," he said computers are still not as reliable or usable as they need to be.

"It falls so far short of what it should be," Gates said, urging further work in areas of artificial intelligence that could allow computers to finally handle long-predicted tasks, such as speech recognition.

The talk was the first stop on a day that will take Gates through the topics of education, philanthropy and industry. At lunch, he received a philanthropy award from Community Foundation Silicon Valley. In the afternoon, he will talk to others in the tech industry in a speech at the Computer History Museum in Mountain View. His trip follows a tour of five East Coast colleges earlier this year.