Hardware

• Magnetic disk


  A storage device that uses a magnetization process to write, rewrite and access data. It is covered with a magnetic coating and stores data in the form of tracks, spots and sectors.
• Quad-core processor


  A chip with four independent units called cores that read and execute central processing unit (CPU) instructions, such as, add, move data and branch. Inside the chip, each core operates in conjunction with other circuits, such as cache, memory management and input/output ports.
• The more cores a CPU has

  The greater the number of instructions it can process in a given space of time
• Many modern CPUs are dual (two) or quad (four) core processors
• This provides vastly superior processing power compared to CPUs with a single core
• Clock speed


  The number of cycles your CPU executes per second, measured in GHz (gigahertz)
• RAM

  A form of computer memory that can be read and changed in any order, typically used to store working data and machine code
• ROM


  A type of non-volatile memory used in computers and other electronic devices
• Random access memory


  Volatile memory that temporarily stores the files you are working on
• Read only memory

  Non-volatile memory that permanently stores instructions for your computer
• Cache memory

  A chip-based computer component that makes retrieving data from the computer's memory more efficient. It acts as a temporary storage area that the computer's processor can retrieve data from easily.
• CPU

  Electronic machinery that carries out instructions from programs that allows a computer or other device to perform its tasks
• Von Neumann Architecture

  • Consists of a single, shared memory for programs and data, a single bus for memory access, an arithmetic unit, and a program control unit
  • The Von Neumann processor operates fetching and execution cycles seriously
• Computer Hardware

  • Processor
  • Memory Devices
  • Monitor
  • Printer
  • Keyboard
  • Mouse
  • Central Processing Unit
  • Motherboard
  • CPU (Microprocessor)
  • Main memory (RAM)
  • Expansion cards
  • Power supply unit
  • Optical disc drive
  • Hard disk drive
• Fetch

  • The retrieval of data by a software program, script, or hardware device
  • After being retrieved, the data is moved to an alternate location or displayed on a screen
• Decode


  To take out of code and put into understandable language
• Execute


  The process by which a computer or virtual machine reads and acts on the instructions of a computer program
• Optical disk


  Any computer disk that uses optical storage techniques and technology to read and write data
• Optical disk


  • It is a storage device for optical (light) energy
  • It is a computer storage disk that stores data digitally and uses laser beams to read and write data
• Compact disks (CDs), digital versatile disks (DVDs), Blu-ray disks


  Provide the highest capacities and data transfer rates of the three
• Processor cores


  Individual processing units within the computer's central processing unit (CPU)
• Processor cores


  1. Receive instructions from a single computing task

  2. Work with the clock speed to quickly process this information

  3. Temporarily store it in the Random Access Memory (RAM)
• Central processing unit (CPU)

  Several functional units
• Functions of the control unit

  1. Controls and monitors communications between the hardware attached to the computer

  2. Controls the input and output of data

  3. Checks that signals have been delivered successfully

  4. Makes sure that data goes to the correct place at the correct time
• Arithmetic logic unit (ALU)


  Performs simple addition, subtraction, multiplication, division, and logic operations, such as OR and AND
• Memory


  Stores the program's instructions and data
• Fetch stage

  1. Computer retrieves a program instruction from its memory

  2. Establishes and carries out the actions that are required for that instruction

  3. Cycle of fetching, decoding, and executing an instruction is continually repeated by the CPU whilst the computer is turned on
• Decode stage

  1. Decoding process allows the CPU to determine what instruction is to be performed

  2. CPU can tell how many operands it needs to fetch in order to perform the instruction

  3. Opcode fetched from the memory is decoded for the next steps and moved to the appropriate registers
• Execute stage

  1. Control unit of the CPU passes the decoded information as a sequence of control signals to the relevant functional units of the CPU

  2. Perform the actions required by the instruction, such as reading values from registers, passing them to the ALU to perform mathematical or logic functions on them
• Reason why manufacturers are finding it difficult to produce processors with clock speeds over 5GHz

  Too much heat is generated which cannot be dissipated fast enough
• Multiprocessor system

  Multiple CPUs
• Multi-core system


  Single CPU with multiple cores
• Multiprocessor system vs multi-core system

  A multi-core processor operates on a single CPU, while a multiprocessor has multiple CPUs
• Advantages of a multi-core processor over a single-core one

  • Allows PCs to run multiple processors at the same time with greater ease
  • May perform significantly better than a single core CPU
• All programs cannot be run twice as fast with a dual-core processor than with a single-core one
• A student describes two differences between RAM and ROM as “RAM is permanent, ROM is read-only”. How many marks would you award this answer out of four?

  • 2

  Justify your score - why did you award those marks?

  • Listed 1 for each of the following, Full marks should include a second difference.

  Now write your own answer to the question

  • The speed of Read-only Memory (ROM) is slower when compared to RAM
  • RAM. Data in RAM can be modified, erased, or read. Data in ROM can only be read.
• How optical discs store binary data

  1. Pits

  2. Lands
• Pits

  Microscopic data pits etched into a reflective layer of recording material
• Lands

  Flat, unindented areas surrounding the pits
• How magnetic drives store binary data

  1. Magnetise tiny individual sections of a metal spinning disk

  2. Magnetised section represents a binary '1'

  3. Demagnetised section represents a binary '0'