To get admission into NIPER Mohali, you need to qualify GPAT. There is no such cutoff rank. You will be eligible to attempt NIPER JEE, only if you qualify for GPAT. NIPER Mohali admissions are based on NIPER JEE rank. The cutoff required in NIPER JEE varies depanding on the course but for getting admission you will have to have a score under 400 if you are from the general category. 

Different colleges have different cutoff requirements. Naturally, you will have better chances of getting admission, if you have a better GPAT score.