I had applied online on NVIDIA website. Got a call for initial phone screen. There were 2 phone screens back to back. First interview consisted of asic,vlsi design,digital design,c coding etc. Second phone interview consisted of computer architecture questions. Both of them went for about an hour. Then got a call for onsite. Onsite consisted of 6 back to back interviews. Each went for about 45 minutes. Question were based on computer architecture(cache,pipelining),fsm design(sequence detector) and the verilog code for the same,synthesis questions, a lot of questions on set up time and hold time,circuit design and puzzles.