NVIDIA Systems Software Engineer interview questions

I recently interviewed for a System Software Engineer position at NVIDIA. The interview was about an hour long and included both coding and system design questions. I felt the interview went well and was able to communicate my approach clearly, so I was surprised to receive a rejection. I would really appreciate any feedback on my performance to understand where I can improve for future opportunities.

I sent an email to the HR I found on LinkedIn, got the reply 2 days after, and received OA after a week. Haven't started the OA, nor the next step if there's any, will update after finishing it.