NVIDIA Software Engineer Interview Experience — Three Onsite Rounds, Rejected Three Days Later

After I passed the one phone screen round, they told me to go straight to the onsite. There were only three rounds in total, which made me realize I wasn't going to be that lucky, and sure enough, three days after the interview I was told I was rejected.
The first round was straight to a director: BQ plus a deep dive. He felt like a smiling tiger, rambling about this and that, and then suddenly started a project deep dive, and not only on my most recent job, he also asked about my earlier experience.
The second round was the most ridiculous. The interviewer set up a virtual machine inside HackerRank, not LeetCode style. I had to hand-write something (or collect) the CPU, memory and disk info, pack it into a JSON payload, and send out a POST request. The POST request went to a server he had built himself. When I sent it, I just kept getting a 403 error. I didn't know at first how to even get info like the CPU, so I had no choice but to google it. The follow-up was to take a threshold before sending and check whether it was exceeded, kind of like a simple sliding window problem. I ran out of time to write it, so I explained it verbally. Overall I stumbled through the whole thing. I'm sure I failed this round. It feels like in a lot of interviews now, verbal follow-ups don't count anymore. I got rejected by Apple the same way before.
The third round was in person at the office. The interviewer was fine, and overall it felt okay: we talked about my projects, then I got one simple LeetCode question.
I don't know why there were only three rounds. Maybe this team is in a hurry to hire and uses this fail-fast approach. Looking back, I don't think I did well. Time to move on, keep going.
Addendum (2026-10-07): There was no system design at all. Before each round I had no idea what I was going to be interviewed on.