There are many fancy add-ons that can be incorporated into a computer, but before these can be installed the basic components of the computer must be connected and operating correctly. If one of these main components is missing the computer will not operate.
The essentials of every computer system are a motherboard, a Central Processing Unit (CPU), memory and a hard drive. These 4 components are installed in a computer case to which are attached a monitor and a keyboard and a mouse. This makes up the basic computer.
The motherboard (sometimes called the mobo) provides the foundation for the rest of the computer components. Everything is attached to the motherboard — the CPU, the memory, the monitor, the mouse, the keyboard, add-on cards, and extra peripherals like printers, scanners, and speakers. We could say that the motherboard is like the nervous system and skeleton of the human body — it provides support for the internal components and also passes information between all the computer parts.
If the motherboard is the nervous system, the CPU is the brain. Most of the mathematical manipulations that make computers operate are done by the CPU. Other components may also have their own processors, but the results still have to be passed through the CPU.
The speed of the computer is usually measured by the speed of the CPU. Even though there are other factors affecting speed, the CPU rating is usually seen the single most important measure of performance.
Modern CPUs are usually rated between 2.0 GHz and 3.0 GHz, although you see some models in the 3.5 GHz range. These numbers refer to the number of calculations the processor can make in one second, so obviously the higher the number the faster the computer.
CPUs generate a lot of heat, so they need a heat sink and fan to prevent them from overheating.
RAM (Random Access Memory) is the part of the computer that stores information while the computer is operating. It is Random Access because the computer can get the stored data in any order, rather than synchronously. Generally speaking, the more RAM the better. 512 to 1024 megabytes is fairly common for memory.
The most common type of RAM these days is DDR-SDRAM which stands for double-data-rate synchronous dynamic random access memory. We already know what the RAM part means. DDR means that the data is accessed at twice the rate than ordinary RAM.
The latest type of RAM is DDR2. It offers even faster access rates that DDR and is quickly becoming the standard for computer memory.
Since the data contained in RAM is lost when the computer is turned off, there has to be a place to store it permanently. This is what the hard disk is for. It also contains all our personal work as well as the operating system. An operating system like Windows uses around 4 gigabytes of hard drive space, and the extra space can be used to install computer programs and to store personal data.
Eighty gigabyte hard drives are the most common, but they are available at up to 400 GB, and several hard drives can be installed in one case.
All that is needed to complete the basic computer system is a monitor, keyboard and mouse. Accessories like a printer or scanner can be useful for office work, and gamers will probably want to add speakers and joystick controls.
So there you have it. The basic computer is composed of just 7 major components. To get the best performance these components must integrate well. The motherboard is the most important component for determining the type and specification of the other parts so choosing an appropriate one for your computer needs is very important.
South African Sources for parts
A very good online source for computer part in South Africa is Simplicity Online
Other local retailers you can check out are NGR Computers or Fruity, a new online retailer