Is TNEA marks alone enough for TamilNadu candidates to join CSIR-CECRI ??

Oh yes. The admissions are through TNEA. I am quoting from the college website - "The Admission is purely on the basis of merit through the single window system, as per rule of the Tamil Nadu Engineering Admission, Anna University Chennai". It is also there in the TNEA college list so you can rest assured that TNEA is the admission window.

If you wish to check the cutoff, the institute has given them for the past years. Check here http://www.cecri.res.in/Academics/GraduateProgramme/Academics.aspx. Scroll down and the details are given there.

Applicant should be a citizen of India and should have studied class VIII onwards in the state other than Tamilnadu. A certificate of Permanent residence in the format given in Annexure-I should be furnished (English version only will be accepted).

The minimum academic requirement is that the applicant must have passed in final examination of 10+2 (Class XII) or its equivalent recognized by any State Board /Central Board or any other Board (other than Tamilnadu) accepted by Anna University, Chennai.

The applicants must have studied Mathematics, Physics and Chemistry as compulsory subjects.

Minimum Eligibility Marks: 50.00 % for General and OBC (NLC); 35.00 % for SC