Government & Defence Entrance Exam

In my opinion, there is no direct relationship between your graduation degree and your rank in CSE. Your rank solely depends on your preparation for the examination and how well grilled you are in the various aspects of the syllabus. The essay paper, the 2 optional papers and the personality test are the key to scoring a good rank in this exam and scoring high in these is absolutely essentially if you need to bag a rank below 100.
There is a chance that your optional paper could also happen to be the same as that your graduation subject - for example, Electrical Engineering (B.Tech), History (B.A) etc. If you have been able to grasp all the nuances of the subject during your graduation studies, it would definitely help you with your preparation for CSE for the same optional subject. But merely your graduation studies would not suffice to score good marks in the optional paper. You would need to do a lot of answer writing practice, analyze the previous year question papers and also study some topics in the CSE syllabus which may not be covered during your graduate degree course.
Some people choose graduate degree courses which are not very time demanding, as they can they can utilize the free time for CSE exam preparation. So if a career in civil services is your ambition, you can choose such a course which would let you spare at least 4 hours a day for CSE preparation. So by the time you would have completed your degree, you have also completed your CSE preparation and can give the exam straight away.Choose the field which you like the most, because CSE first requires you to be a professional in your field before you sit for services. Professionalism is what distinguishes civil servants from the remaining staff. You better long far that. Remember that the commission never expects you to be a academician or expert in GS, they just check for basic know and most importantly run tests to see if you possess the qualities a officer needs, as simple as that.

There are numerous government organisations which recruit the candidates with B.Tech in Information Technology. Some of them are NIC, ERNET India, HARTRON, STPI, BHEL, ISRO, OBGC, VSSC, CDAC, SAIL, NTPC, etc.
Bank -You can apply for Bank jobs like Probationary Officer and for IT-Officer and many more jobs in the bank also.
Civil Services - You are eligible for the IAS, IPS like Civil services after graduation in Computer Science.
Central Defense Academy- You can apply for CDS. This Exam is conducted by UPSC twice in a year for recruitment in the army.
You can begin their career as a junior engineer in these firms. Then you can get promotion as chief engineer or senior engineer after clearing various tests in the department. On comparison with private firms, the salary in government firms is less, but the government firms compensate with allowances. The initial salary in any government firm is Rs.15000/- to Rs.25000/- per month. The salary will increase with experience to nearly Rs. 75,000/- to Rs. 80,000 per month with experience.
You can get a list of government IT jobs from this link: http://www.indgovtjobs.in/2014/04/it-fresher-jobs.html
B.E./B.Tech courses in the branches of Computer Science & Engineering and Information Technology (IT) will have tremendous employment opportunities in the coming years since the IT sector is set to grow till 2020 according to the Indian Statistical Department.
As per the Microsoft research analysis, 1.5 million software engineers would be required in the next four years. More than 90% of the placed students of self-financed engineering colleges are placed only in the IT industry.
The job opportunities are going to increase as more and more development takes place globally in the fields of IT. As you can see, IT is a very vast field which offers opportunities from Computers to Telecom, Space, Defense and many more sectors. After doing B-tech in computer science you will get lots of job options to make a blooming career. It entirely depends on you whether you want to do a job or go for higher study.