hi,

see gate exam is the gate way exam to take admission in nits or iits or iiits or any other reputed college of India , even some of the abroad university consider gate score for admission for ms course. now In india you have two options after clearing gate score, you may either go for psu job or do mtech . now see for as for the past years recruitment records, most of the psu recruits for electrical, mechanical and electronics and communication engineering stream, as for the eligibility criteria for reputed psus for electronics engineers, candidate must have valid score in gate ece paper and have completed btech on ece stream, however in some interdisciplinary work profile cse/ece/ee all are allowed. so if you want to do job in psu you should appear in gate exam from ece stream since it has more recruitment than cs. as per the previous years records cse has less recruitment in gate exam, and for companies like iocl, ongc eligibility for cse is, candidates must complete btech in cse stream and must have valid gate score in cse.

so if psu job is your main concern then you should appear in gate from ece stream, other wise for mtech course cse would be fine.