the first round consisted of aptitude and technical.second round was gd .common topics of fiserv are is gd should be an elimination round or not? next round is technical pi.it mainly focuses on your resume.and your programming skills next up is managerial round.mainly focus on your problem solving skills and creativity.last round is hr round .simple they will ask about you,your background.make sure your resume should be true to oneself. focus on c if you want to get hired.they basically demands c and definetly fiserv is one of the most emerging company.