Computer Hardware Components Notes for SSC Exams

Computer hardware is the physical part of a computer, and SSC asks about the motherboard, the BIOS, the GPU and the power supply. These computer hardware components notes for SSC explain every important component with tables and practice questions. Read it with the Computer Fundamentals Notes and Secondary Storage Devices Notes notes.

What Is Hardware?

Hardware means all the physical parts of a computer that we can touch. The main groups are the input devices, the output devices, the processing unit (CPU), the memory and the storage devices. Inside the cabinet (the system unit) there are the motherboard, the CPU, the RAM, the storage drive and the power supply.

Important Internal Components

BIOS and CMOS

• BIOS (Basic Input Output System) is firmware stored in ROM. It starts the hardware check (POST) and loads the operating system when the computer is switched on.
• CMOS (Complementary Metal Oxide Semiconductor) is a small memory that stores the BIOS settings, date and time. It is powered by a small battery.
• The newer replacement of BIOS is UEFI (Unified Extensible Firmware Interface).

Expansion Slots and Buses

Hardware Terms to Remember

• A cabinet or system unit is the box that holds the main parts.
• A peripheral is any device connected to the computer from outside, such as a keyboard or a printer.
• Plug and play hardware works as soon as it is connected.
• A device driver is the software that lets the OS work with a hardware device.
• Overclocking means running the CPU faster than its rated speed.
• A UPS (Uninterruptible Power Supply) gives battery backup when the power fails.

Motherboard in Detail

Motherboard sizes are called form factors: ATX (standard), micro-ATX and mini-ITX (small).

Processor and Cooling

• The main CPU makers are Intel and AMD. Intel series: Core i3, i5, i7 and i9 (and Xeon for servers). Smartphones mostly use ARM-based chips.
• A CPU needs a heat sink and a fan (or liquid cooling) because it produces heat. Thermal paste improves the transfer of heat.
• The CPU is placed in a socket; modern CPUs have several cores and a built-in cache.
• Overclocking raises the speed beyond the rated limit and increases heat.
• An APU is a processor with a built-in GPU.

Graphics and Sound

Power Supply and Protection Devices

System Unit Parts and Computer Care

• The cabinet (case or tower) holds the motherboard, drives and the SMPS.
• The front panel has the power button, reset button, USB ports and the audio jacks.
• Drive bays hold the hard disks and the optical drives.
• The SMPS fan and the case fans keep the air moving.
• Keep the computer in a dust-free and cool place and clean the dust regularly.
• Always shut down the computer properly and do not disconnect a drive while it is working.
• Handle the components with care, because static electricity (ESD) can damage them.

Booting Sequence in Short

1. The power button is pressed and the SMPS supplies the power.
2. The CPU starts the BIOS or UEFI firmware.
3. POST checks the CPU, RAM, keyboard and other devices.
4. The firmware finds the boot device (hard disk or SSD).
5. The bootloader loads the operating system into the RAM.
6. The OS starts and shows the login screen.

Important Questions Explained

Question 1: Which is the main circuit board of a computer?
Answer: The motherboard.

Question 2: What is the full form of SMPS?
Answer: Switched Mode Power Supply.

Question 3: Which chip stores the start-up instructions of a computer?
Answer: The BIOS (in ROM).

Question 4: Which component processes images and video?
Answer: The GPU (Graphics Processing Unit).

Question 5: Which battery keeps the date and time when the PC is off?
Answer: The CMOS battery.

Question 6: What does a UPS provide?
Answer: Battery backup during a power cut.

Quick Tips to Remember

• Remember the motherboard as the "mother" that holds all the parts.
• Link BIOS with ROM and start-up, and CMOS with settings and a battery.
• Remember SMPS as the part that converts AC to DC.
• Link GPU with graphics and video.
• Remember that peripherals are external devices.

Common Mistakes to Avoid

• Writing the CPU as the main circuit board.
• Confusing the BIOS (firmware) with the CMOS (settings memory).
• Mixing the SMPS with the UPS.
• Writing the hard disk as the main memory.
• Thinking that a keyboard is an internal component.

Quick Revision Points

• Motherboard = main board; CPU = brain; RAM = temporary memory.
• BIOS = start-up firmware in ROM; CMOS = settings and clock with a battery.
• SMPS = AC to DC; UPS = battery backup.
• GPU = graphics processing.
• Peripherals are external devices.

Practice Questions With Answers

1. The main circuit board of a computer is?
   Answer: Motherboard (System board).
2. BIOS is stored in which memory?
   Answer: ROM (Firmware).
3. SMPS converts?
   Answer: AC into DC (Power supply).
4. Which unit processes the graphics?
   Answer: GPU (Graphics card).
5. What keeps the date and time after switching off the PC?
   Answer: CMOS battery (BIOS settings).
6. What does UPS stand for?
   Answer: Uninterruptible Power Supply (Battery backup).
7. The bus that carries memory addresses is the?
   Answer: Address bus (One-way).
8. Which card connects a computer to a network?
   Answer: NIC (Network interface card).
9. A device attached from outside the computer is called?
   Answer: Peripheral (Keyboard, printer).
10. What is the replacement of BIOS called?
    Answer: UEFI (Unified Extensible Firmware Interface).

More Practice Questions With Answers

1. Which company makes Core i3, i5 and i7 processors?
   Answer: Intel (CPU).
2. What is the standard motherboard size called?
   Answer: ATX (Form factor).
3. Which paste improves heat transfer to the heat sink?
   Answer: Thermal paste (Cooling).
4. What is the voltage of mains power in India?
   Answer: 230 V (AC).
5. What is a processor with a built-in GPU called?
   Answer: APU (AMD).
6. Which UPS always runs the load from the battery?
   Answer: Online UPS (Clean power).
7. Which device protects from voltage spikes?
   Answer: Surge protector (Power protection).
8. Which card connects a computer to a network?
   Answer: NIC (Network interface card).
9. What can damage components through a static charge?
   Answer: ESD (Electrostatic discharge).
10. Which memory belongs to the graphics card?
    Answer: VRAM (GPU).
11. Who are the major GPU makers?
    Answer: NVIDIA and AMD (Graphics).
12. Which chip stores the start-up firmware on the motherboard?
    Answer: BIOS or UEFI chip (Firmware).

How to Practise This Chapter

1. Read the tables once and learn the key facts by heart.
2. Revise the quick revision points the next day.
3. Attempt the practice questions above without looking at the answers.
4. Solve a full SSC CGL Tier 1 mini mock to test your general awareness.
5. Check the previous year papers to see how SSC asks computer questions.

Related Notes and Practice Papers

• Computer Fundamentals Notes
• Secondary Storage Devices Notes
• Computer Ports and Connectors Notes
• Computer Knowledge Notes for SSC
• SSC CGL Tier 1 Mini Mock

Explore More SSC Subjects

SSC exams test many subjects, so connect this topic with the related subjects below:

• General Science Notes
• General Awareness Notes
• Quantitative Aptitude Notes
• Reasoning Notes
• Electrical Engineering (SSC JE) Notes
• All SSC subjects and notes

Frequently Asked Questions

What is computer hardware?

Hardware is the physical part of a computer that we can touch, such as the CPU, the motherboard and the monitor.

What is a motherboard?

The motherboard is the main circuit board that connects all the parts of the computer.

What is BIOS?

BIOS is firmware stored in ROM that starts the hardware and loads the operating system.

What is the difference between BIOS and CMOS?

BIOS is the start-up program in ROM, while CMOS is a small memory that stores the settings and the clock with a battery.

What is the function of SMPS?

SMPS converts the AC supply into the DC supply needed by the computer parts.

What is a GPU?

A GPU is the graphics processing unit that processes images and videos.

What is a peripheral device?

A peripheral is an external device connected to a computer, such as a printer or a keyboard.

What is a UPS?

A UPS is a device that gives battery backup when the power fails.

How many questions come from hardware in SSC exams?

One or two questions usually come from the hardware parts.

What is the difference between a UPS and a stabiliser?

A UPS gives battery backup when the power fails, while a stabiliser only keeps the voltage steady and does not give backup.

What is a form factor?

A form factor is the standard size and shape of a motherboard or case, such as ATX or mini-ITX.

What is integrated graphics?

Integrated graphics means that the GPU is built into the CPU or the motherboard instead of being a separate card.