STUDY MATERIAL · GATE CS
GATE Computer Organization: questions and notes
Computer Organization and Architecture questions from 10 GATE papers (2018–2026) with the official answers, 57 of 58 solved step by step, plus notes for each topic, a formula sheet and practice questions.
- previous-year questions
- 58previous-year questions
- solved step by step
- 57solved step by step
- GATE papers, 2018–2026
- 10GATE papers, 2018–2026
- topics with notes
- 5topics with notes
TOPICS
Five topics, in the order they are taught
Taken from the official GATE 2027 syllabus. Each topic has notes, the formulas you need, its previous-year questions with the official answers, most of them solved step by step, and practice questions.
Instruction sets and addressing modes
Instruction sets and addressing modes define how a CPU encodes which operation to perform and where its operands are.
11 previous-year questions · 18 marks · 5 practice questions
ALU design and the control unit: hardwired and microprogrammed
A CPU executes an instruction as a sequence of register transfers.
5 previous-year questions · 6 marks · 5 practice questions
Memory hierarchy, performance and cache mapping
A memory hierarchy gives the processor close to cache speed at close to main-memory cost per bit, and it works because programs show locality of reference.
22 previous-year questions · 39 marks · 5 practice questions
I/O interface: interrupts and DMA
I/O interfacing bridges the speed gap between a fast CPU and much slower I/O devices.
8 previous-year questions · 8 marks · 6 practice questions
Instruction pipelining and pipeline hazards
Instruction pipelining overlaps the execution of successive instructions by splitting the datapath into stages.
12 previous-year questions · 20 marks · 5 practice questions
QUESTIONS BY TOPIC AND YEAR
58 questions, by topic and year
How many questions each topic had in the CS papers of each year. This shows what was asked, not what will be asked. We placed each question under a topic ourselves; the exam paper does not label topics. Every question links back to its paper.
| Topic | 2018 | 2020 | 2022 | 2023 | 2024 | 2025 | 2026 | Total |
|---|---|---|---|---|---|---|---|---|
| Instructions & addressing | 2 | 1 | · | 1 | 2 | 2 | 3 | 11 |
| ALU & control unit | · | 2 | 1 | · | · | 2 | · | 5 |
| Memory & cache | 2 | 3 | 3 | 2 | 4 | 4 | 4 | 22 |
| I/O, interrupts & DMA | 1 | 1 | 1 | 1 | 2 | 1 | 1 | 8 |
| Pipelining | 1 | 1 | 1 | 1 | 3 | 2 | 3 | 12 |
GATE CSE question papers with solutions: 2026 Set 1, 2026 Set 2, 2025 Set 1, 2025 Set 2, 2024 Set 1, 2024 Set 2, 2023, 2022, 2020, 2018
The 2019 and 2021 papers are not included: the copies we host are scans. GATE 2023 comes from IIT Kanpur's own copy of the paper and its answer key, which numbers the CS questions Q.11 to Q.65. For 2024, 2025 and 2026 both sessions (CS1 and CS2) are included.
Computer Organization formulas by topic
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THE OFFICIAL SYLLABUS
What each paper lists under Computer Organization and Architecture
From the GATE 2027 syllabus PDF: CS Section 3, “Computer Organization and Architecture”. Number representation and floating-point arithmetic are listed under Section 2, Digital Logic, not here.
GATE CS
Instruction set and addressing modes. Design of arithmetic and logic unit (ALU). Design of control unit – hardwired and microprogrammed. Memory interfacing and hierarchy: performance, cache memory mapping. I/O interface (interrupt and DMA). Instruction pipelining, pipeline hazards.
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