It was part of campus placement. They had a strict percentage of marks criteria and it was followed by an Aptitude test. It consist of aptitude questions, C/C++ questions, Data Structure related problems, but most of it contained Operating System questions. 100 Questions and 2 hours. Followed by technical interviews and HR interview at NVIDIA office. Tech interview had mostly C/DS questions, they make you write code for sorting/searching algorithms, OS and micro processor related programs were also asked.