GCSEComputer ScienceOCRExam Questions1. Systems ArchitectureCPU Architecture, Performance & Embedded Systems

CPU Architecture, Performance & Embedded Systems (OCR GCSE Computer Science): Exam Questions

Exam code: J277

1 hour17 questions
Easy
Medium
Hard
1a
1 mark

The specification of two CPUs is shown in Fig. 1.

Computer 1

Computer 2

Clock Speed: 1 GHz

Clock Speed: 1.4 GHz

Cache size: 2 MB

Cache size: 2 MB

Number of Cores: 4

Number of Cores: 2

Fig. 1

When running a 3D flight simulator, Computer 1 is likely to run faster than Computer 2.

Using the information in Fig. 1, identify one reason for this.

How did you do?

1b
2 marks

Identify two other parts of a computer that are not in Fig. 1, which could improve the performance of the computers.

How did you do?

2
2 marks

Identify two events that take place during the fetch-execute cycle.

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3a
1 mark

A Sat Nav contains an embedded system.

Define what is meant by an ‘embedded system’.

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3b
3 marks

Identify three devices, other than a Sat Nav, which contain embedded systems.

How did you do?

4
2 marks

Von Neumann architecture includes registers.

Identify two registers used in Von Neumann architecture.

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5
4 marks

Match the letter in the definitions to the part of the processor it describes

Definitions

A

Performs mathematical operations

B

Sends signals to direct the operations

C

Keeps the clock in sync

D

A small piece of memory inside the processor that can hold one instruction or address

E

High speed memory inside the processor that stores recently used instructions

Part of the processor

Control Unit (CU)

Cache

Arithmetic Logic Unit (ALU)

Register

How did you do?

6
1 mark

Draw one line from each part of the processor to its correct definition.

A table with processor parts on the left: Control Unit (CU), Cache, Arithmetic Logic Unit (ALU), Register, and definitions on the right, partially mismatched.

How did you do?

1
4 marks

Complete the table by writing the missing definition or name of each of the common CPU components and registers.

CPU component or register

Definition

Stores the address of the next instruction to be fetched from memory. Increments during each fetch-execute cycle.

CU (Control Unit)

Stores the address of the data to be fetched from or the address where the data is to be stored.

Performs mathematical calculations and logical operations.

How did you do?

2
2 marks

Explain one reason why the cache size affects the performance of the CPU.

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3a
1 mark

A computer system has a 2.5 GHz processor and 5 GB of RAM.

State the purpose of a CPU.

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3b
2 marks

State what is meant by a single core 2.5 GHz processor.

How did you do?

4
3 marks

Ali’s tablet computer has an operating system.

Ali thinks his tablet is an embedded system.

State whether Ali is correct or incorrect, justifying your choice.

How did you do?

5a
1 mark

Xander has a smart watch and a laptop.

Tick (✓) one box to show whether the smart watch or the laptop is an example of an embedded system.

Is an example of an embedded system

Smart watch

Laptop

How did you do?

5b
2 marks

Justify your choice to part (a).

How did you do?

6a
4 marks

Alicia has designed a computer using Von Neumann architecture.

Describe the purpose of two registers that are used by Von Neumann architecture.

How did you do?

6b
2 marks

The CPU has a clock speed of 3.8GHz.

Describe what is meant by a clock speed of 3.8GHz.

How did you do?

7a
2 marks

A computer has a Central Processing Unit (CPU).

Describe what happens during the fetch-execute cycle.

How did you do?

7b
4 marks

Name two registers used in the fetch-execute cycle and the purpose of each register.

How did you do?

7c
3 marks

Give three characteristics of a CPU that can affect its performance.

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8
3 marks

A car has a ‘Follow Me’ system that uses a cruise control feature to allow the car to follow the car in front of it. It will keep the same speed and distance without the driver’s intervention. The cruise control system is an example of an embedded system.

Explain the reasons why the ‘Follow Me’ system is an example of an embedded system.

How did you do?

9
4 marks

Complete the table by writing the missing definition or name of each of the common CPU components and registers.

CPU component or register

Definition

Temporarily stores data and instructions that are frequently accessed by the CPU to reduce access time to main memory.

ALU (Arithmetic Logic Unit)

A small, high-speed storage location within the CPU that holds data temporarily during processing.

Manages and coordinates all CPU operations by sending control signals to other components.

How did you do?

1a
5 marks

Kerry wants to buy a new computer, but she does not understand what the different parts of a computer do.

Kerry has heard of a CPU but does not know what it is.

The following sentences describe the purpose of a CPU.

Complete the sentences by filling in the missing words.

CPU stands for .....................................

It is the part of the computer that fetches and executes the

.................... that are stored in ...........................

The CPU contains the Arithmetic ............ Unit (ALU) and the

............. Unit (CU).

How did you do?

1b
2 marks

Kerry is looking at two computers; one has a single core processor and the other has a dual core processor.

Explain why having a dual core processor might improve the performance of the computer.

How did you do?

1c
2 marks

One computer has 64 kilobytes of cache and the other has 512 kilobytes of cache.

Explain how the cache size can affect the performance of the CPU.

How did you do?

2
3 marks

Alicia says:

“My computer has a quad-core processor, so it will run twice as fast as a computer with a dual-core processor.”

Explain why this statement is not always true.

How did you do?