I know there's no official cutoff GPA. But I'm sure there must be some point where your GPA is low enough that you have very little, if any, chance. Specifically, I am asking to get into an experimental AMO / CM program, especially at a top 10 school. Of particular interest are UChicago, Berkeley, Columbia, Maryland and UWashington. Of less personal interest but just curiosity are Harvard, MIT, Stanford, Caltech and Princeton.
I am just asking you guys for your personal gut instinct and intuition. I can't get a straight answer from my department.