after joining a it company does the increase in salary for a graduate who has scored higher package happens more than a graduate who have got less salary if they are from the same college
See as you join a IT company, after joining the promotions and increments are entirely dependent on your performance as well as the yearly increment ration fixed by the company. Thus if you perform better or if the company feels that giving you a promotion worth it then you will obviously get promotions and appreciation from the company but for that you have to work really hard.
I hope this answer helps. All the very best for your future endeavors!