Start with pondicherry(some 180kms from chennai). Get in touch with Auroville Ashram and get an accommodation there. Once you have spent sometime there you can move to Chennai and then to Bangalore.
I second this. With or without Auroville, Pondicherry is awesome. Have decent internet connectivity, living cost is low and peaceful with all big city facilities in a small town.
Edit:- But no start up culture or any events worth participating. You can visit Auroville, of course.
Edit:- But no start up culture or any events worth participating. You can visit Auroville, of course.