Computer Organisation & Architecture carries roughly 7-9 marks in every GATE CS paper, and almost all of it arrives as arithmetic: cycles for n instructions through a stalled pipeline, average memory access time across two cache levels, tag and index widths for a given configuration, disk access time from geometry.

This course is built around that fact. Twelve topics walk the machine from instruction encoding through the datapath, control unit, pipeline and its hazards, the memory hierarchy, cache organisation and performance, virtual memory, secondary storage and I/O — and the final topic is nothing but exam drill: numerical-answer sets, past-paper walkthroughs and timed sectional practice.

Every lesson carries audio narration, so you can revise a topic without reading it.