The computer system is a unit composed of several components that are referred to as computer hardware. These are the devices that assist the user to input data and commands, processing them and then storing them for later use. An operating system is ultimately responsible in managing the computer hardware. These include the processor, memory input and output devices and buses are the components that compose of the computer hardware. Engineering in Kenya has more information.
Components of Computer Hardware in a Personal Computer
A personal computer is composed of a processor as a computer hardware that its works is to fetch instruction from memory and execute them. The processor found in the central processing unit in the components of computer hardware in personal computers has a specific set of instructions that it can execute. The basic cycle of every central processing unit is to fetch instruction from memory, decode it to determine its type, and operands execute it and the fetch decode and execute subsequent instructions in this way program are carried out. The processor as component of the computer hardware in the personal computer is capable of executing more than one instruction at the same time unlike the earlier the central processing units.
The second major component among the computer hardware in the personal computer is the memory. The memory is constructed in a hierarchy of layers which consist of the registers, cache, main memory, magnetic disk and magnetic tapes. The memory is responsible for the storage data, instruction and information in the components of computer hardware.
Hierarchy of Memory in Components of Computer Hardware
The top layer in the memory as a component of computer hardware consists of the registers. The registers, internal to the central processing unit, are made of the same material as the central processing. The register in the components of the computer hardware is very fast in the memory hierarchy, there is no delay in accessing them, and has a low data capacity about less than 1kilobyte among the layers of memory in the components that makeup the computer hardware of modern personal computer.
Next is the cache memory among the layers of memory in components of computer hardware. The cache memory is controlled by the computer hardware and it is limited in size due to its high cost. Due the difference in the type of computer hardware in different computer system, some machine have even two or three levels of cache each one slower and bigger than one before in the computer hardware.
Main memory comes next in the hierarchy of memory in the components of computer hardware. This is the work house of the memory system known as the Random Access Memory (RAM). All central processing unit requests that cannot be satisfied in the cache memory are sent to the main memory. The main memory or random processing memory is known to be volatile; it cannot hold data for long, for example in the computer hardware when power goes off data that is held in the random access memory is lost permanently.
After the main memory in the hierarchy of memory in the component of computer hardware is the magnetic disk also known as hard disk. The disk storage is two orders of magnitude cheaper than the random access memory per bit and often two orders of magnitude layer as well. The disk consists of one or more metal platters that rotate at 7200 or 10800 rpm and velocity 15000rpm as one of the component of computer hardware.
The final layer in the memory hierarchy is magnetic tape in the components of computer hardware. This medium is often used as a backup for disk storage and for holding very large data. In additional to this kinds of memory many computer hardware have several types of magnetic disk also referred to as Read Only Memory (ROM) which is non volatile. Electronically Erasable Programmable Read Only Memory (EPROM) and flash random access memory are also non volatile but in contrast to read only memory can be erased and written again which are among the computer hardware.
Another kind of memory is the CMOS in the memory component of the computer hardware. The CMOS memory is volatile and it holds the current time and date and also the configurations parameters for example disk to boot from. The device in computer hardware that performs the checks and mapping of the memory is called memory management unit. In the computer hardware is the memory management unit is capable of converting the virtual address to physical address.
Other Component of Computer Hardware in Personal Computer
The input and output devices are also one of the components that make up the computer hardware. The input and output devices consist generally of two parts; the controller and the device itself. Each controller is different and different software is needed to control each one. The device driver is the software that takes the controller giving it commands and accepting responses in the computer hardware.
The other type of component of computer hardware in modern personal computer is the bus. The bus is a special kind of wire that consists of several wires that are capable of transmitting data at the same time once. The structure of modern computer hardware has eight buses; cache, local, memory, peripheral component interconnector (PCI), small computer system interface (SCSI), universal serial bus (USB), integrated drive electronic (IDE) and industry standard architecture (ISA). Each type of bus has its type of process that it executes in the computer hardware.
Consideration while choosing Computer Hardware
When choosing the type of computer hardware suitable for any kind of job one should take into consideration several factors. One of the main factors is the processor of the computer system in terms of its speed, and the ability of multiprogramming and multitasking. The other important aspect in considering the type of computer hardware suitable is the memory. The memory of computer system is very important in terms of its retrieval speed and the capacity of storage. However the compatibility of the input and output devices with the other component of the computer system is also very important factor to consider while choosing the suitable and appropriate computer hardware to use.