Hiiii naveen...

with the increasing competition the cutoff as well the score at which you are promised a govt college also increases every year !

first lets talk of the government colleges

the current situation is that if you score below 500 there is no chance in getting anything through the central counselling whatsoever. few chances though the state quota are also very week !

if it ranges between 520 to 550 you will get a govt seat through the centralized all India counselling conducted by MCI online , for sure to get a govt seat through your state quota!

private colleges

where big money(above 75 lakh rupees) is involved you can get a seat at any score till you are above the 50th percentile(which is a very low mark )

where it is affordable to most there is still competition , we spare Maharashtra and Madhya pradesh because these states have a complete state quota on  reputed institutions like comedk and manipal are still hard to get for comedk anything above 480 would promise a decent seat in a decent college