Shortlisting on GPA basis..
top 5 (General) and top 2 (OBC) were shortlisted from mech..
top 2 from General and 2nd from OBC finally got selected
My rank was 1
Candidates Selected from Mechanical:
Manav Vohra (GE)
Ankit Bagla (GE)
Vinay Chowdhary (OBC)

Technical:
Questions were based on the following topics:
Thermodynamics
IC Engines
Power Plant Engineering (Most Imp.)

HR:
Self Introduction
Family Introduction
Why NTPC?
Whether you would like to publish papers on your work at NTPC? (Tricky Question)

Most Importantly, try to be among the toppers. It is a myth that NTPC takes only top 1 or top 2 and only GPA is needed. All the top 5 shortlisted have good chances of making it. Your technical knowledge, confidence and the body language holds the key!!

Secondly, if you have done training at NTPC before, make sure that you are thorough with that plant's functioning and every aspect of your training.

Thirdly, go through the website of NTPC thoroughly, sometimes the HR questions can be really demanding and one needs to have sound knowledge of the company's operations and its diversification.

Just Stay calm and cool during the interview.. Prepare well and no one can stop u!!

Shortlisting was don on the basis of OGPA upto 5th semester
This was followed by a HR cum Technical Interview....
The following factors, I believe, worked for me:
1. Topper of the Batch
2. Sound Technical Knowledge of the concerned fields. (Most Imp.)
3. Impressive Body Language

There was a person in the panel only for observing the body language, posture, confidence etc. He was fof the Psychometric test of the candidate.