Computers 101: An Overall Guide to Understanding and Building Computers

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Computer components and parts.

This is part one of a series of computer articles designed to supply the average user with enough information to understand their own computer. This will help said user from being scammed by an increasingly bold tech industry, which is realizing its ability to trick the general public into thinking that computers are too difficult to understand, and then charging outrageous prices for computer parts and their repair. ( It is always cheaper to build and repair your own computer. )

Computers today are mercifully simple in comparison to computers of the past. There used to be a day when one required an abundance of tools, dexterity, and knowledge to build a computer. Now, computers are dominated by simple slots and cables; so much so that they resemble legos. Before that, operating systems had to be custom made. Even before that, computers had to be hard-wired for whatever tasks they were to perform. Now, we have *NIX type operating systems, Windows, and OS X; all of which are common amongst many computers with different hardware. We also have CPUs with instruction sets that can carry out enough tasks to accomplish virtually anything we could ask for in a computer. Modern computers are so simple, in fact, that if I write a separate article for each of these computer components, ( as I intend to ) they should contain enough cumulative information to build a computer, clock the components, troubleshoot them, do in-depth testing on them, and install them individually. ( I can not make an article out of all of these, as some are impractical, but I should be able to write one for most. )

  1. Motherboard -  Hosts the components of the computer. They may have things like integrated graphics and audio. ( Also called onboard graphics and audio. )
  2. Monitor - This displays images generated by the computer.
  3. Chipset - A group of ICs ( Integrated Circuits ) that are designed to work together to accomplish tasks. This frequently refers to just the northbridge, southbridge, and CPU on the motherboard.
  4. Northbridge - Also known as MCH ( Memory Controller Hub ), and IMC ( Integrated Memory Controller ). This handles communication between the CPU and high-speed components, such as the main memory, AGP, PCI-E graphics cards.
  5. Southbridge - Also known as ICH ( I/O Controller Hub ) or PCH ( Platform Controller Hub ). This handles communication between the CPU and slower components, such as PCI bus, PCI-E, PCI-X, LPC bridge, ISA bus, SMBus, SPI, DMA controller, real-time clock, IDE controller, APM or ACPI, nonvolatile BIOS memory, AC97 or Intel HDA sound interface, and the baseboard management controller. ( The reason I won't write an article about each of these is because even the majority of advanced users will not hear much about some of these, as they usually come installed on other parts and are impractical to install yourself. )
  6. CPU - Also known as the Central Processing Unit. This generally does four things: fetch, decode, execute, and writeback. It does these in sets as required by programs. The four CPU functions will be explained more thoroughly in a future article.
  7. DRAM - This is referred to as the main memory, usually just called the RAM. ( Although there are many kinds of RAM which are not used for main memory. ) This stores temporary data that needs to be read and manipulated more quickly than with HDDs and SSDs.
  8. HDD - Also known as Hard Disk Drive, or just Hard Drive. This stores large quantities of data for long periods of time. Unlike DRAM, this does not require power to store data it already has.
  9. SSD - Also known as Solid State Drive. This stores large amounts of information for long periods of time like a HDD, but differs in the way it works, which will be discussed more thoroughly in a future article.
  10. Graphics card - Also known as the video card. This processes the graphics for things like games, simulations, and desktop environments. Some computers don't have them, as they have integrated graphics.
  11. Audio card - Also known as the sound card. This converts digital data into an analog format, whether in or out. Some computers don't have these either, for the same reason as graphics cards.
  12. Networking card - Also known as network adapter, network interface card, LAN adapter, and NIC. ( Network Interface Controller )  This enables your computer to connect to a ( usually ethernet ) network interface. There are also wireless network adapters for wireless networks.
  13. CMOS - This either refers to the CMOS RAM, or the CMOS battery. The CMOS RAM is a still common, but outdated form of RAM that houses the BIOS and uses little power.
  14. CMOS battery - This powers the CMOS RAM and system clock when the computer is off. If the computer is newer and uses EEPROM or flash memory for the BIOS, it will just power the system clock.
  15. AGP - Also known as Accelerated/Advanced Graphics Port. This is used to attach a graphics card to a motherboard. It has been mostly phased out by PCI ports.
  16. PCI local bus - Also known as Peripheral Component Interconnect. This is used to attach peripheral devices with the motherboard. PCI-X and PCI-Express are faster versions, but PCI is still popular.
  17. PSU - Also known as Power Supply Unit. This converts alternating current to direct current, which is needed for components of the computer.
  18. Heatsink - This draws heat away from computer components that generate a lot of it, such as the CPU or graphics card.
  19. BIOS - Also known as Basic Input/Output System.This is the first code a computer runs when it is turned on. It is used to recognize, test, and activate hardware devices so that other software, most commonly operating systems, can be given control of the computer.
  20. OS - Also known as Operating System. This provides an interface after the BIOS. It also provides an interface between the different hardware components and ways for the user to operate the computer. It also hosts software designed for it. They usually come with a desktop environment.

Here are pictures to help you recognize the different components. Open them to get a closer look.


A motherboard. These can vary in dimensions, components, and color.

One of many chipsets.

A northbridge covered with a heatsink. ( As they usually are. )

A southbridge covered with a heatsink. ( As they also usually are. )

A CPU. These generally look the same.

The main memory, in the form of DRAM. This is very easy to recognize and almost always looks exactly the same, unless it has a heatsink.


A HDD. These generally look the same, unless they are external. You will normally see them with the case on.

A SSD. These are generally recognizable.


A graphics card. These vary in size, color, and whether or not they have a fan. They always have a fan or heatsink, though, making them recognizable from most sound cards.

A sound card. These lack a heatsink or fan in my experience, and always have input and output connectors in the form of a hollow cylindrical tube.

Three different network cards. As you can see, these can vary greatly. They should be recognizable because of an antenna or ethernet port. 

A CMOS chip. These can vary in the way they look. The average user will rarely need to know what this looks like, but I intend to discuss it more in a later article.

A CMOS battery. You will most likely need to be able to recognize this more than the CMOS chip. It usually looks just like this.


An AGP ( maroon ) and PCI ( white ) slot. These always look the same.

A PSU. These usually look the same.

A heatsink ( under the fan ) for a CPU. These can vary depending on what they are designed for, how large they are, and what they are made out of. They are easy to recognize, however.

A BIOS screen. These can vary in how they are laid out, and what options they have. 


Three different desktop environments for three different operating systems: GNU/Linux, Windows 7, and OS X ( Mac ) respectively.

Note that just because I used a picture of a specific brand, doesn't mean it is any good.

                                                                                           ---###SOURCES###--- - For BIOS. - For CPU. - For Chipset. - For CMOS. - For PCI. - For HDD. - For Motherboard. - For network cards. - For CMOS RAM. - For Northbridge. - For OS. - For main memory. - For audio card. - For graphics card. - For SSD. - For PSU. - For AGP. - For CMOS battery.





1 comment

Mark Cruz
Posted on Feb 7, 2012