As you want to get the details of syllabus of Public Sector Units and the GATE exam so here is the information of the same for you:

By PSU exam you get the job in public sector union companies like BHEL, HAL, NTPC and many more.

Their syllabus are totally different they check from you your technical knowledge, general awareness question, aptitude problems.

Whereas in Gate exam they ask objective type problem regarding the syllabus of engineering (which you have choosen), it's totally depend on your technical knowledge whatever you learn in you engineering life from 1st year to final year.