the minimum percentage for the OBC category cannot be calculated as because it will be turn on the relative performance of the different reserved and unreserved candidates in a particular area which internal depend on the level of the question paper for that particular year but on an average you can say that any marks used for in excess of 450 should be good to go if you just want a seat in any private or government medical or dental college but specifically if you want the government medical college c then as an OBC candidate you need to score in excess of 480 to 500 and as an OBC candidate for 15% all India quota medical seat in government college in a state where you don't have domicile you need to score in excess of 530 to 570 depending on which state you want admission into