At Intel, I was responsible for a special project.
You have to say "special" project to make it have importance.
You could mention what the project was "special new microprocessor project"
To mention "Interning" you could say:
During my internship at Intel, I was responsible for a special project.
Instead of "responsible for" you can say "managing"
At Intel, I was managing a special project.
You could give more detail:
At Intel, I was managing a special project for the mobile development unit.
Hope this helps...