A PhD from a top engineering school helps. Actually, dropping out of a PhD program in computer science and/or another form of engineering from a top school helps. The degree itself means little to nothing in Silicon Valley and to investors. But the fact that you were admitted to such a selective program is a big deal. And the program matters. Stanford is perceived as highly entrepreneurially oriented. In fact, the President of the University sits on the boards of Apple and Google – and his thesis when he was at Stanford was all about how useless PhDs are – that is, the computing world changes so fast, it doesn't make any sense to try to get all “philosophy” on it. Nobody can predict anything – so just code. Build stuff. Let Adam Smith and the marketplace rule.
So Stanford is the top dawg by a mile; Yes, Harvard and others have great, smart people. But they don’t have the same cowboy culture of Stanford, which now has a vastly long history of supplying brains to the Beast. Good luck gettin’ in.