If you think you might quit architecture, but stay in the design field, go to RISD.

If you think you might quit architecture and design, go to UT Austin.

If you're sure that you will stay in architecture, it's a tough choice. They are both great programs. It really depends on how you consider yourself.

RISD will focus more on studio work, rigorous manual drawings and model-making. The foundation program is a great experience through which you can identify yourself as a designer/artist, and discover your true interests. Switching between majors is pretty easy, so if you want to become a designer of any sort, it will be better to pick RISD. However, if you want to become a tech-wiz, you need to reach out and learn it outside classes.  

For UT Austin, I don't know anything about the school. It's just that in gradschool I met a few students who went there, and they produced great work. They seem more computer-savvy and knowledgeable regarding academics and technical things than RISD grads in my opinion. Also a wider variety of friends is an advantage. At an art school (although I enjoyed my every second at an art school) it is difficult to be friends with a potential client.

How many art schools did you apply to, and how many universities? If there's a big difference in numbers between the two, that might hint at where your intuitive preferences are.