The system unit
The system unit, or the chassis, contains the components that the computer uses to function - Computer basics introduction. It contains the main components: the motherboard, the processor, memory, adapter cards, ports, drive bays and the power supply. While the motherboard contains chips and adapters that enable the components to communicate and function as required; the processor is the seat of the control and arithmetic logic unit that logically directs and manages the commands and operations of the components.
More Essay Examples on Computer Rubric
The machine cycle of the central processing unit, or processor is as follows: First, it receives the command or raw data from the memory. Then the raw data is translated and processed at the control unit. Once the command is ready to be executed, it is forwarded to the ALU or arithmetic logic unit. Finally, the processed information or command is stored at the memory, ready to be accessed and used.
The register is temporary storage that holds data and instructions while simultaneous processes are undergone. The pace of processes is determined by the system clock. More clock cycles per second (one gigahertz equals one billion ticks per second) means processes are executed faster (189).
Comparison of personal computer processors, buying a personal computer/Putting It All Together
Data passes into several digital pathways to undergo processing. The capacities of RAM, clock speed, data on storage devices affect processing speed. Computer processors are categorized according to clock speed. A prospective computer buyer needs to consider the tasks and functions intended in using the computer so that the appropriate components can be bought. Home and small office users who use basic word processing and simple data management software need a minimum processor of Celeron D, Pentium 4, Sempron or Athlon 64 and 256-512mb RAM. Large businesses with multiple departments and more human resources accessing information need atleast Pentium D or Athlon 64 FX and 1 GB of RAM. Multinational corporations whose international operations store and process thousands of information need atleast Xeon MP, Itanium 2, Athlon MP or Opteron and 2 GB of RAM.
Heat sinks/heat pipes/liquid cooling
Cooling devices are used to keep the system from overheating: The heat sink cools the processor; the heat pipe is a smaller cooling device used in laptops; and liquid coolers use fluids to continuously transport heat away from the processor.
As the need for increased efficiency arises, parallel processing is utilized to perform multiple programs at the same time.
Computers make use of the binary system, 1 and 0, in accessing and storing data. A byte, referred to as the volume of data, is a combination of eight bits. Bytes of data are further grouped into codes that correspond with the different commands the computer is capable of processing. To date, there are three commonly used coding systems: American Standard Code for Information Interchange (ASCII), Extended Binary Code Decimal Interchange Code (EBCDIC) and Unicode.
Random access memory or RAM temporarily holds data from the CPU to a storage device and vice versa. The more RAM, the more temporary data can be kept in standby. RAM is measured by the bytes it is capable of storing: one kilobyte is one thousand bytes while one gigabyte is one billion bytes. Low RAM leads to more frequent data swapping which reduces the computer’s performance especially if several programs or big files are opened. RAM provides the computer processor with temporary storage for programs and data. All data must be transferred to RAM before it is processed. When simultaneous applications are being accessed by a user, all operating instructions are stored in RAM. So if the computer gives a warning that there is no sufficient memory, the user has to close an application or two to continue using the other open applications. The computer does not have enough memory to run all the applications initiated. Instructions and data will only be removed from RAM when an application is closed or when the computer is turned off. Basic types of RAM are: Dynamic RAM (DRAM) and Static RAM (SRAM). SRAM uses less energy and is faster and more reliable than DRAM.
Other types of memory
The memory cache stores data and instructions that are often used. Thus, increases the computer’s processing speed. Depending on the model, memory cache may be built in the processor and the motherboard.
The Read-only memory (ROM) stores permanent data and instructions comes in three types: firmware, PROM and EEPROM. Firmware comes with most electronic devices. It is where the instructions and data for the device’s operation reside. PROM or programmable read-only memory allows a user to encode data and instructions permanently while EEPROM or electronically erasable programmable read-only memory allows a programmer to erase previously written information.
Complementary metal-oxide semiconductor memory or CMOS uses battery to maintain the computer’s date, time and startup information. The processor accesses the memory in nanoseconds or one billionth of a second. In a matter of a fraction of a second, a computer can process requested information or open multiple applications.
Expansion slots and adapter cards
Depending on the motherboard model, expansion slots can accommodate peripheral/external devices to complement the computer. External devices range from modems, network cards, video and sound cards to graphic accelerators. Some devices have features that allow users to automatically use them as they are plugged.
Portable storage devices
Increasing mobility requirements of people have brought about the popularity of flash drives and memory cards. These portable storage devices act as the computer’s extra storage and allow data to be conveniently transferred from digital cameras, diaries and laptops to desktop computers and vice versa.
Ports and connectors
Expansion slots are linked to ports and connectors where the external devices are attached. There are unique connectors for every computer peripheral. Except for the audio, video and speaker connectors, all of the connectors will accept only the compatible peripheral suitable for it. Users need not worry about the complex connectors behind the chassis.
Peripherals that do not need high speed data transmission are connected through ports. These are the mouse, keyboard and modem. While the printer and monitor are connected through a parallel port to transfer more data at a time. The universal serial bus or USB port allows different kinds of external devices to be connected with a single type of connector.
The firewire port connects multiple devices that need high speed data transfer. Finally, special ports are designed for Musical Instrument Digital Interface (MIDI), Small Computer System Interface (SCSI), Infrared or Bluetooth connection.
Buses, bays and Power supply
Buses and expansion buses serve as data highways between the processor, the RAM and the other components including the peripherals. The bus width controls the speed of data transferred.
Additional system components such as CD, DVD and hard drives can be placed on drive bays.
Electricity is used to power up the computer through the AC-DC power supply. Along with the system devices, a fan also uses power to keep the components from overheating. External peripherals use adapters in using external power supply.
Mobile computers and devices
As mobility proves to be in demand these days, mobile computers and devices have gained popularity. Students are now equipped with mobile phones while most business professionals have PDAs. The notebooks laptops or tablet PCs are also common among people who bring work and leisure wherever they go.
Keeping computer clean
The interior as well as the exterior of the computer needs cleaning. Utmost care must be practiced in dusting and greasing the components of the computer.