COMPUTER MAINTENANCE AND SUPPORT July 2018

192/2018
COMPUTER MAINTENANCE AND SUPPORT
July 2018
Time: 3 hours

THE KENYA NATIONAL EXAMINATIONS COUNCIL
CRAFT CERTIFICATE IN INFORMATION TECHNOLOGY
MODULE II
COMPUTER MAINTENANCE AND SUPPORT
3 hours

INSTRUCTIONS TO CANDIDATES
The paper consists of TWO sections, A and B.
Answer ALL the questions in Section A and FOUR from Section B in the answer booklet provided.
Candidates should answer the questions in English.

This paper consists of 4 printed pages.
Candidates should check the question paper to ascertain that all the pages are printed as indicated and that no questions are missing.
© The Kenya National Examinations Council Turn over

SECTION A (40 marks)
Answer ALL the questions in this section.

1. Explain the term ‘post’ as used in computer monitors.
ANSWER: POST (Power-On Self-Test) is a diagnostic testing sequence run by a computer’s BIOS to check if the hardware components are working correctly before the operating system loads.

2. Describe ‘sector’ as used in magnetic disks.
ANSWER: A sector is the smallest unit of data storage on a magnetic disk, usually 512 bytes in size.

3. Differentiate between ‘DRAM’ and ‘SRAM’ as used in computer memory.
ANSWER: DRAM (Dynamic Random Access Memory) requires periodic refreshing of its data to retain it, while SRAM (Static Random Access Memory) retains its data as long as power is supplied, without needing to be refreshed.

4. With the aid of examples, explain the role of an address bus in a computer.
ANSWER: The address bus carries the addresses of data (not the data itself) between the processor and memory. For example, when the CPU needs to read or write data to a memory location, the address bus specifies the location.

5. Outline four functions of a power supply unit in computers.
ANSWER:

  • Converts AC power from the mains to DC power for the computer.
  • Regulates the voltage supplied to different components.
  • Provides necessary power to the motherboard, drives, and peripherals.
  • Protects the computer from power surges or spikes.

6. Explain two reasons for discarding old computers upon incoming innovations.
ANSWER:

  • Incompatibility with new software or hardware.
  • The inefficiency of old systems in handling modern, resource-intensive tasks.

7. Distinguish between cold and warm restarts as applied to devices in computers.
ANSWER:

  • Cold restart involves turning the computer off completely and then back on, clearing the memory and resetting the system.
  • Warm restart restarts the computer without turning off the power, allowing for faster reboots.

8. Explain two circumstances under which the main memory of a computer would be replaced.
ANSWER:

  • When the main memory becomes faulty or corrupt.
  • When the memory is insufficient for the system’s needs, requiring an upgrade.

9. Patricia was required to troubleshoot a computer monitor that was displaying the ‘ghosting’ effect. List three possible causes of the problem.
ANSWER:

  • Poor quality or damaged video cables.
  • Incorrect monitor refresh rate settings.
  • Outdated or corrupted video drivers.

10. Explain three classifications of computers according to physical size and processing speed.
ANSWER:

  • Microcomputers: Smallest and used for personal computing, e.g., desktops.
  • Minicomputers: Larger than microcomputers and used by small businesses.
  • Mainframes: Powerful machines used by large organizations for bulk data processing.

11. Denis intends to carry out computer literacy training for his employees. Explain five benefits the company could realize after training.
ANSWER:

  • Increased productivity due to improved efficiency in using computers.
  • Reduced errors from better understanding of software and hardware.
  • Better decision-making through improved data handling.
  • Enhanced communication through the effective use of email and office tools.
  • Competitive advantage as the workforce becomes more tech-savvy.

SECTION B (60 marks)
Answer any FOUR questions from this section.

12.

(b) Paul was advised by his friend to replace a faulty processor for his computer. Explain three possible causes of the problem.
ANSWER:

  • Overheating of the processor due to inadequate cooling.
  • Physical damage to the processor or its socket.
  • Electrical surges or improper power supply.

(c) List two types of computer keyboard interfaces.
ANSWER:

  • USB interface.
  • PS/2 interface.

(d) Distinguish between ‘core’ and ‘CPU’ as used in computers.
ANSWER:

  • A core is a single processing unit within the CPU that can execute instructions.
  • The CPU (Central Processing Unit) is the complete chip with multiple cores responsible for executing programs.

13.

(c) Explain three circumstances under which an organization should consider conducting an urgent computer maintenance exercise for its computers.
ANSWER:

  • When there is a virus or malware outbreak.
  • When hardware components start malfunctioning frequently.
  • When the system’s performance drops significantly, indicating possible hardware or software issues.

14.

(d) Explain three strategies that could be used as a remedy for this attack.
ANSWER:

  • Implementing stronger password policies.
  • Installing antivirus software and firewalls.
  • Regularly updating software to patch security vulnerabilities.

15. (a) Outline three functions of the BIOS chip.
ANSWER:

  • Initializes and tests hardware components during the boot process.
  • Loads the operating system from the hard drive or other storage.
  • Provides low-level communication between the hardware and operating system.