First round was the Aptitude Test- It was an adaptive test. Covered general aptitude question and lots of questions on Series based questions. (Eg. find the missing number, complete the following series)
The second round was an English Assessment Test. Proper use of punctuation, format of the formal letter, correct use of articles, prepositions, conjunctions, were tested.
The third round was the HR round. Questions asked were general HR questions- "Tell me something about yourself, past projects you have worked upon, tell me about your strengths and weaknesses, why IBM? "