Hi Chandru.R

As per your cutoff score and previous year cutoff, the colleges you get in third or fourth round are:-

Easwari Engineering College,Thiruvallur

KPR Institute of Engineering and Technology, Coimbatore

St. Josephs College of Engineering ,Kancheepuram

KSR Institute for Engineering and Technology ,Namakkal

AVS Engineering College ,Salem

VSB Engineering College ,Karur

Sri Krishna College of Enginering and Technology - Autonomous    Coimbatore

To know more about your other colleges check out this college predictor link:

https://engineering.careers360.com/tnea-college-predictor

Yes Absolutely !! you are eligible. In order to secure a seat at a engineering college in Tamil Nadu, you need to clear TNEA (Tamil Nadu Engineering Admissions) exam. The eligibility to sit for the exam is 40% aggregate marks in 12th class in Physics, Chemistry and Mathematics for the reserved category students . Since you have scored over the required percentage you are eligible for taking up engineering.

The cut off marks for TNEA will be fixed by the Anna University to shortlist the candidates for further rounds of the admission process. You need to secure the minimum qualifying marks decided by the university.  Percentage of seats reserved for SC under TNEA :

Scheduled Caste - 15% , Scheduled Caste (Arunthathiyars) - 3%

Please check the following link which contains the cutoff of various colleges that falls under the gambit of TNEA.

https://engineering.careers360.com/articles/tnea-cutoff

All the best !!!