Components of a Computer

a dell mordern laptop

motherboard of a CPU

CPU and its components

interior of a Desktop



full view of a CPU compoents



labelled diagram


Yesterday i promised to feature components of a system well i did and i hope i have broken it down enough.
Do feel free to notify me of my errors and please do comment, it gives me the sense someone out there likes what i do.

Microcomputer System Components and Their Functions

Computers are made up of thousands of electronic chips, resistors, capacitors, diodes, and other pieces that all work together to run your computer programs. To make it easier to grasp how a computer works, the pieces are grouped together into components. The components are the major building blocks of your PC.

System Components
Every make and model of PC has a slightly different layout for its components. Rather than trying to memorize details of one system, concentrate on the big picture of general computer organization so you can adapt to different situations with a variety of computers.

System Board

The system board is the main circuit board in a microcomputer. The system board is the principal printed circuit board in a computer. It is a very thin plate which has chips and other electrical components on it that make up the CPU (Central Processing Unit), the computer memory, and basic controllers for the system. Sometimes called the motherboard, the system board has some electrical components soldered directly to it, and slots and sockets where components can be added and removed easily. The wires that connect the soldered components, the slots, and the sockets are all permanently built into the system board. Usually the microprocessor, or CPU, is on a large chip that is held in a socket on the motherboard so you can upgrade the chip when a compatible, new chip comes out. The chips that control the flow of information to and from the CPU are usually soldered to the system board and are not replaceable. The jacks where you plug in the mouse and keyboard are usually soldered to the system board, but the network and modem connections are usually on interface cards that are easily inserted and removed from slots on the system board. Because features that are built into the design of the system board cannot be changed without replacing the whole system board, most system boards include only the standard features that most users want; that will not change much in the near future. By leaving off features that many users do not use, like SCSI and network connections, the cost of the board is kept down. By allowing the users to buy the modem with the speed and features they want, and letting the users attach the card to the motherboard, the designers build in flexibility that most users appreciate. Sometimes computer makers who sell complete systems find it is cheaper to build a system board with the modem, sound card, video and all other features built in, rather than add interface cards to a standard system board. The buyers of these complete systems get a low price but give up the freedom of easily upgrading and customizing the computer. Because system boards must be replaceable, they all come with certain standard features. Unfortunately, the standards for these features change over time. For example, the system board usually has slots that hold cards full of memory chips, rather than having the chips soldered directly to the board. You can increase the memory of your computer by replacing the memory cards with cards with more capacity. Every few years, though, a completely new style of memory card will appear that will not fit into the old-style slots. At that point, you either need to buy a new system board or miss out on the advantages of the new-style memory cards.
System boards are often described by their general physical characteristics. The original motherboard design was the AT, which was 12 inches wide. A smaller Baby AT board, 9 inches wide by 10 inches long, became popular after 1989 when the demand for small computers increased. New processor chips required a redesigned system board, and in 1996 the ATX design was introduced. This system board was 12 inches wide by 9.6 inches long, while the Baby ATX was about an inch shorter in both width and length. The ATX board design took into account the need to cool the CPU and memory chips, and the need to move highspeed components as close together as possible to reduce errors as the extremely high-speed signals move across the system board. The CPU must be mounted on a card which is inserted into a special slot on the ATX board, rather than inserted into a socket on the system board. Another way to classify system boards is by the set of chips on the board that support the CPU, or its chip set. When buying or working on a computer, you must know the general design of the system board, the make and model of the processor on the board, and the kind of chip set that is on the board.

Processor

The microprocessor, sometimes called just the processor or the CPU (Central Processing Unit) is the real brains of the computer where most of the calculations take place. On very large computers, the CPU may consist of many chips mounted on a series of printed circuit boards, but on personal computers, the CPU is housed in a single microprocessor chip. The microprocessor is divided into areas, the first of which retrieves programmed instructions from the computer’s memory, decodes, and executes the instructions. The second area is the arithmetic and logic unit (ALU) that does the math operations when need. The third area sends the results back out to the rest of the computer.
Many companies make microprocessors for IBM-compatible personal computers (PCs), but Intel CPUs are the ones against which the other companies’ CPUs are compared and rated. The original IBM PCs were based on Intel’s 8086 CPU. Other models followed over the years, including 80286 (commonly called the 286), the 386, and the 486. Each of these processors came in a variety of configurations. Because Intel couldn’t own the name 486 for a processor, it used a name it could trademark, Pentium, for its 586 processor and Pentium Pro for its 686 equivalent processor. Many of the microprocessors come in different varieties that run at various clock rates. New Intel chips can run all the programs written for earlier models, but old processors cannot run programs that make use of the special features found only in the newer processors. Cyrix and AMD are two of the companies that make Intel-compatible chips that are often less expensive than Intel and sometimes offer better performance. Intel Inside, however, is a selling point used by many computer manufacturers. Because Intel microprocessors and the Windows operating system are found together on so many machines, some people refer to those PCs as Wintel. Even though other operating systems can run on Intel processors, and some Windows operating systems run on non-Intel chips, the popularity of the combination is overwhelming.

Memory
Memory refers to the internal storage areas in the computer. In common usage, memory refers to actual chips that keep track of computer data, and not the information stored on tape or hard drives. Memory chips contain millions of transistors etched on one sliver of semiconductor. These transistors either conduct electricity and represent the binary number 1, or don’t conduct electricity and represent the binary number 0.

RAM (Random Access Memory) is the main memory. The computer can both read the data stored in RAM memory, and write different data into the same RAM memory. Any byte of data can be accessed without disturbing other data, so the computer has random access to the data in RAM memory. RAM memory requires a constant source of electricity to keep track of the data it is storing. If the electricity is cut off, RAM forgets everything. Because of this, RAM memory is described as volatile memory. DRAM (dynamic RAM) is the most common type of RAM. DRAM must be refreshed thousands of times per second. SRAM (static RAM) does not need to be refreshed. SRAM is faster, but more expensive, than DRAM, but both forms of RAM are volatile. ROM (Read-Only Memory) refers to special permanent memory used to store programs that boot the computer and perform diagnostics. ROM also allows the computer random access to data in its memory. More importantly, the computer cannot change any of the data stored on the ROM, so ROM is read-only memory. In the early personal computers, you added more memory by fillings empty sockets on the motherboard with more memory chips. A SIMM (Single In-line Memory Module) made adding memory easier because all the chips were soldered to a single, small printed circuit board that you inserted into a slot on the system board of your computer. SIMMs transfer information 32 bits at a time, while DIMMs (Dual In-line Memory Modules) transfer data 64 bits at a time. Pentium processors require a 64-bit path, so you must add either two SIMMs at a time or one DIMM to a Pentium computer. CMOS RAM is special memory that has its own battery to help it keep track of its data even when the power is turned off. CMOS memory stores information about the computer setup that the computer refers to each time it is turned on. Because you can write new information to CMOS RAM, you can store information about new disk drives that you add to your system. The computer will remember to look for the drive each time it is turned on.

Interfaces

An interface on a computer is a place where you can connect another device like a disk drive, keyboard, modem, or mouse. Sometimes the interface connection is built into the system board, like the mouse port and keyboard port. Sometimes the actual connector is on a printed circuit card that adapts the signals to and from the attached device so it can communicate with the computer. Modems, which are constantly improving, are generally on an interface card.
Interface cards are inserted into a slot on the system board that connects to the microprocessor. The collection of wires that make the connection, and the rules that describe how the data should flow through the wires, is called a bus. The ISA (Industry Standard Architecture) bus connects to ISA slots that accept only ISA cards. The ISA slots were used on early IBM computers and became the industry standard. As computers became faster, they needed buses that could transfer more data, more quickly, than the ISA bus could handle. The PCI (Peripheral Component Interconnect) local bus solved this problem, although only new PCI cards could be used in the PCI slots on the system board. Most computers have a combination of ISA and PCI slots on the system board.
Next time i would be picking this components singlely and feature its importance to the system