Intel Corporation Software Engineer Intern interview questions

I got call from Hiring Manager for interview , there were total of 4 interviews all telephonic by different people from different location. first interview was behavioral by hiring manager , most of the questions were about my previous experience , mostly on the work i done and projects i worked on , then some related to my academic project and research work, no specific question but general descriptive, and then at the end why this company related few question. second was with 3 senior members , i think 2 were senior engineer and one interviewer was of director level , mostly grilled on my projects and then specific questions on C++ and OpenGL programming and then what projects i would be interested in company if i given choice ,this was important i believe. 3rd interview was taken by junior engineer and lead , question were related to vector calculations , graphics and basic C++ programming questions. final interview was again related to vectors and then some tricky questions on my previous work projects that how did i do (e.g. how did you actually improved performance for games - driver tweaks etc) and then i was offered intern position for 6 months.