Hello Aspirant,

See it is quite difficult to guide you with an accurate marks range for any specific rank because there is no any fixed marks pattern for JEE-Advance  but however if you are seeking All India Rank under then you should aim for at least 50% or more marks of the total marks in JEE-Advance. As you belongs to OBC category then on such rank you can get following IITs with CSE branch :-

Indian Institute of Technology Bhubaneswar

Indian Institute of Technology Mandi

Indian Institute of Technology Indore

Indian Institute of Technology Hyderabad

Indian Institute of Technology Gandhinagar

Indian Institute of Technology Patna

Indian Institute of Technology Roorkee

Indian Institute of Technology (ISM) Dhanbad

You can check out previous year's cut-offs for IITs from the link given below :-

https://josaa.nic.in/Result/Result/currentorcr.aspx

Note that the above prediction is made on the basis of previous year's cut-off and the cut-offs are bound to change every year depending upon various factors such as the number of candidates appearing in an examination, the number of candidates qualifying an examination, difficulty level of the paper, and so on.

To have a list of all those colleges which you can get based upon your marks, category, and state you can use JEE-Advance College Predictor:-

https://engineering.careers360.com/jee-advanced-college-predictor?icn=QnA&ici=qna_answer

I hope this information helps you.

Good Luck!!