That depends on the school. Non-selective schools that “buy in” top students (to borrow tsbna’s phrase) may look only at GPA and test scores. But at selective schools that give very limited, very competitive full ride merit scholarships (examples: Robertsons @ Duke, Stamps at GT and UMich, Banneker-Key at UMD) the decision process is holistic and ECs are a big component. Other than at GT, test scores are optional.
@curryeater, congratulations on your impressive accomplishments!