Computer Architecture and Components: A Deep Dive

Computer Architecture and Components

A computer is a digital device that accepts information and manipulates it for some result based on a program, software, or sequence of instructions on how the data is to be processed.

Basic Elements of a Computer

  • Hardware: Consists of tangible objects, the physical parts of the computer.
  • Software: Consists of algorithms and their computer representations: programs.

Evolution of Computers

  • First Generation:

    ENIAC. It consisted of 18,000 vacuum tubes and 1,500 relays. It weighed 30 tons and consumed 140 kilowatts. It was programmed by setting up 6,000 multi-position switches and connecting a multitude of sockets with a veritable forest of jumper cables. To change a program, it was necessary to change the physical connections. The program should be represented in digital form in the computer’s memory, along with the data.

  • Second Generation:

    Use of transistors. The bus was introduced, which is a collection of parallel wires used to connect the components of a computer. This architecture was a major departure from the memory-centered machine and has been adopted by nearly all small computers since.

  • Third Generation:

    Use of silicon integrated circuits (ICs). The invention of ICs allowed dozens of transistors to be put on a single chip.

  • Fourth Generation:

    Very Large Scale Integration (VLSI). Combining millions of transistors onto a single chip. Processors.

  • Fifth Generation:

    Is more a paradigm shift than a specific new architecture. Are based on artificial intelligence (AI), natural language processing, parallel processing, and ULSI technology.

Hardware

Physical parts.

Motherboard

The most important component of the computer. Provides a physical interface for the interconnection of the other elements. Allows communication between elements using a bus.

CPU

Processor. Computer brain. It handles large amounts of data and performs calculations at high speed. It:

  • Receives data from the input peripherals.
  • Processes data and runs programs.
  • Sends the results to the output peripherals.

It has a special socket which is placed below the fan.

RAM Memory

It is a high-speed memory which is capable of storing the programs and data required by the CPU during the execution of a program.

  • Read/Write memory.
  • Volatile memory: Data is lost when the power is turned off.
  • Two main technologies: SRAM and DRAM.

It is placed on the motherboard, via dedicated sockets, in 1, 2, 4, 6, or even 8 socket configurations. When the CPU requires information from the hard disk, it must be loaded into RAM memory.

BIOS

It is a memory which stores a program to initialize the physical components when the computer is turned on. It is also in charge of checking these components to find possible errors.

Chipset

Manages communications between the processor and the other elements of the motherboard. It has to be compatible with the CPU. Formed by two chips: Northbridge and Southbridge.

Ports

Connectors that allow the interconnection of different elements with the computer to be controlled by the CPU.

Motherboard Inner Ports

  • SATA port: Allows the connection of hard drives and SSD units to the motherboard. It is faster, reaching data transfer rates of 600MB/s.
  • PCI/PCI express: For connecting expansion cards.

External Ports

  • PS/2: Keyboard and mouse.
  • Parallel: Printers.
  • Serial: Monitors, printers.
  • USB: Peripherals.
  • RJ-45: Ethernet connection.
  • VGA, HDMI, DVI: Monitor connection.
  • Mini-Jack: Audio connectors.

Expansion Cards

Extend the functionalities of the PC. They are connected to the motherboard via dedicated sockets. Relevant expansion cards:

  • Sound card: Audio device. Three types:
    • Integrated into the motherboard.
    • Onboard, connected to the motherboard using a PCI slot.
    • External, connected via USB port.
  • Graphics card: Manages procedures related to graphics generation. Two types:
    • Integrated into the motherboard and uses the RAM memory of the PC.
    • Onboard, connected to the motherboard using a PCI-express slot, and it has its own memory.
  • Network card: Allows the connection to the internet or to other PCs. Three types:
    • Integrated into the motherboard.
    • Onboard (Wi-Fi), provides wireless internet connection.
    • Onboard (Ethernet), it uses the RJ45 connector to connect to the Ethernet or to a private network.

Peripheral Devices

External devices, provide additional functionalities. Allow the PC to communicate with the outside world.

  • Input peripherals: Allow data to be entered into the PC.
  • Output peripherals: Allow the PC to send information to the outside world.
  • Input/Output peripherals: Allow the introduction and extraction of information from the PC.

Software

Is intangible. Functionalities: Data treatment, Communication management between the user and the PC, Resource management and optimization.

Types

  • Operating system: Main software of the PC system. It manages hardware resources, programs, and applications. Intermediary between the user and the PC. Translates our instructions into digital language and vice versa. Types: Private and free.
  • Drivers: Each peripheral device has a specific program which needs to be installed in order to allow the operating system to communicate and control the device.
  • Apps: Software packages intended for the execution of specific tasks. Types: free and commercial.

Computer Architecture

Is a branch of engineering that is responsible for the design, manufacture, and improvement of computers.

Bus System

The components are connected through a bus, which is a collection of parallel wires for transmitting address, data, and control signals: data bus to carry information, address bus to determine where it should be sent, control bus to determine its operation, commands and status signals. Buses can be external to the CPU, connecting it to memory and I/O devices, but also internal to the CPU.

Internal Memory

Main memory is the only one directly accessible to the CPU. Four main types of primary memory:

  1. Register Memory: Just 32 or 64 bits.
  2. Cache Memory: Small and fast, Volatile, Stores frequent program instructions, Can be CPU integrated or a separate chip.
  3. Random Access Memory (RAM): Volatile, Stores data loaded by active programs and the operating system, Connected to the central processing unit via a memory bus.
  4. Read-Only Memory (ROM): Non-volatile, Used in the computer start-up process.

External Memory

Not connected directly to the CPU. Uses an I/O Bus. Types of secondary memory: HDD, SDD.