I got scores between 750 and 780 on my SAT Subject Tests in Math 2 and Physics. Will I be able to get into schools like Stanford, Caltech, and the Ivies as a CS major with these scores? Should I retake either or both of the tests?
Yes, you will most likely be able to get into these schools with your current scores. Students scoring above a 750 on subject tests are competitive applicants at the most selective colleges in the country.
If you want to have even better chances of admission, you might consider retaking one or both of the tests and shooting for an 800. As a computer science applicant, you’ll want to emphasize your skills in Math specifically, so an 800 on Math 2 could improve your odds considerably (especially if you’re going for schools like Caltech or MIT, which are looking for the most talented math and science students).
I'd also recommend thinking about other achievements that you can emphasize on your application besides test scores. If you're interested in computer science, maybe you could try building an app or online tool of some sort. If there's anything you've accomplished in high school that ties into what you plan on doing in college, make sure you put it front and center on your application. These selective colleges are interested in students with passion, not just perfect scores!