the main circuit board of a microcomputer

8/4/2019 The Main Circuit Board of a Microcomputer

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What is mother board:-

The main circuit board of a microcomputer. The motherboard contains the connectors forattaching additional boards. Typically, the motherboard contains the CPU, BIOS, memory,

mass storage interfaces, serial and parallel ports, expansion slots, and all the controllers

required to control standard peripheral devices, such as the display screen, keyboard, and

disk drive. Collectively, all these chips that reside on the motherboard are known as the

motherboard's chipset.

On most PCs, it is possible to add memory chips directly to the motherboard. You may also

be able to upgrade to a faster PC by replacing the CPU chip. To add additional core features,

you may need to replace the motherboard entirely.

(1)
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PCI slots:-

PCI (part of the PCI Local Bus standard and often shortened to PCI) is a

computer bus for attaching hardware devices in a computer. These

devices can take either the form of an integrated circuit fitted onto the

motherboard itself, called aplanar device in the PCI specification, or an

expansion card that fits into a slot.

PCI cards used in PCs include: network cards, sound cards, modems, extra

ports such as USB or serial, TV tuner cards and disk controllers.Historically video cards were typically PCI devices, but growing bandwidth

requirements soon outgrew the capabilities of PCI. PCI video cards remain

available for supporting extra monitors and upgrading PCs that do not

have any AGP or PCI Express slots.

BIOS chip:-
http://en.wikipedia.org/wiki/Computer_bushttp://en.wikipedia.org/wiki/Computer_hardwarehttp://en.wikipedia.org/wiki/Computerhttp://en.wikipedia.org/wiki/Integrated_circuithttp://en.wikipedia.org/wiki/Expansion_cardhttp://en.wikipedia.org/wiki/Network_cardhttp://en.wikipedia.org/wiki/Sound_cardhttp://en.wikipedia.org/wiki/Modemhttp://en.wikipedia.org/wiki/Universal_Serial_Bushttp://en.wikipedia.org/wiki/Serial_porthttp://en.wikipedia.org/wiki/TV_tuner_cardhttp://en.wikipedia.org/wiki/Disk_controllerhttp://en.wikipedia.org/wiki/Video_cardhttp://en.wikipedia.org/wiki/Accelerated_Graphics_Porthttp://en.wikipedia.org/wiki/Computer_bushttp://en.wikipedia.org/wiki/Computer_hardwarehttp://en.wikipedia.org/wiki/Computerhttp://en.wikipedia.org/wiki/Integrated_circuithttp://en.wikipedia.org/wiki/Expansion_cardhttp://en.wikipedia.org/wiki/Network_cardhttp://en.wikipedia.org/wiki/Sound_cardhttp://en.wikipedia.org/wiki/Modemhttp://en.wikipedia.org/wiki/Universal_Serial_Bushttp://en.wikipedia.org/wiki/Serial_porthttp://en.wikipedia.org/wiki/TV_tuner_cardhttp://en.wikipedia.org/wiki/Disk_controllerhttp://en.wikipedia.org/wiki/Video_cardhttp://en.wikipedia.org/wiki/Accelerated_Graphics_Port


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The BIOS of PC software is built into the PC, and is the first code run by a

PC when powered on ('boot firmware'). The primary function of the BIOS is

to load and start an operating system. When the PC starts up, the first jobfor the BIOS is to initialize and identify system devices such as the video

display card, keyboard and mouse, hard disk, CD/DVD drive and other

hardware. The BIOS then locates software held on a peripheral device

(designated as a 'boot device'), such as a hard disk or a CD, and loads and

executes that software, giving it control of the PC.This process is known

as booting, or booting up.

SERIAL PORT:-

a serial port is a serial communication physical interface through which

information transfers in or out one bit at a time (contrast parallel

port).Throughout most of the history ofpersonal computers, data transfer

through serial ports connected the computer to devices such as terminals

and various peripherals.

PARALLEL PORT:-

A parallel port is a type of interface found on computers (personal and

otherwise) for connecting various peripherals. In computing, a parallel

port is a parallel communication physical interface. It is also known as a

printer port or Centronics port. The IEEE 1284 standard defines the bi-

directional version of the port, which transmits data bits at the same time
http://en.wikipedia.org/wiki/Personal_computerhttp://en.wikipedia.org/wiki/Operating_systemhttp://en.wikipedia.org/wiki/Video_display_cardhttp://en.wikipedia.org/wiki/Video_display_cardhttp://en.wikipedia.org/wiki/Hard_diskhttp://en.wikipedia.org/wiki/Serial_communicationhttp://en.wikipedia.org/wiki/Bithttp://en.wikipedia.org/wiki/Parallel_porthttp://en.wikipedia.org/wiki/Parallel_porthttp://en.wikipedia.org/wiki/Personal_computerhttp://en.wikipedia.org/wiki/Computer_terminalhttp://en.wikipedia.org/wiki/Computershttp://en.wikipedia.org/wiki/Personal_computerhttp://en.wikipedia.org/wiki/Computinghttp://en.wikipedia.org/wiki/Parallel_communicationhttp://en.wikipedia.org/wiki/Centronics#The_interfacehttp://en.wikipedia.org/wiki/IEEE_1284http://en.wikipedia.org/wiki/Personal_computerhttp://en.wikipedia.org/wiki/Operating_systemhttp://en.wikipedia.org/wiki/Video_display_cardhttp://en.wikipedia.org/wiki/Video_display_cardhttp://en.wikipedia.org/wiki/Hard_diskhttp://en.wikipedia.org/wiki/Serial_communicationhttp://en.wikipedia.org/wiki/Bithttp://en.wikipedia.org/wiki/Parallel_porthttp://en.wikipedia.org/wiki/Parallel_porthttp://en.wikipedia.org/wiki/Personal_computerhttp://en.wikipedia.org/wiki/Computer_terminalhttp://en.wikipedia.org/wiki/Computershttp://en.wikipedia.org/wiki/Personal_computerhttp://en.wikipedia.org/wiki/Computinghttp://en.wikipedia.org/wiki/Parallel_communicationhttp://en.wikipedia.org/wiki/Centronics#The_interfacehttp://en.wikipedia.org/wiki/IEEE_1284


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(in "parallel"). This is the opposite of serial transmission where one bit is

transmitted at a time.

USB PORT:-

USB (Universal Serial Bus) is a specification to establish

communication between devices and a host controller (usually personal

computers), developed and invented by Ajay Bhatt while working for

Intel.USB is intended to replace many varieties ofserial and parallel ports.

USB can connect computer peripherals such as mice, keyboards, digital

cameras, printers, personal media players, flash drives, and external hard

drives. For many of those devices, USB has become the standard

connection method. USB was designed for personal computers, but it has

become commonplace on other devices such as smart phones, PDAs and
http://en.wikipedia.org/wiki/Serial_cablehttp://en.wikipedia.org/wiki/Ajay_Bhatthttp://en.wikipedia.org/wiki/Serial_porthttp://en.wikipedia.org/wiki/Parallel_porthttp://en.wikipedia.org/wiki/Computer_peripheralhttp://en.wikipedia.org/wiki/Mouse_(computing)http://en.wikipedia.org/wiki/Computer_keyboardhttp://en.wikipedia.org/wiki/Digital_camerahttp://en.wikipedia.org/wiki/Digital_camerahttp://en.wikipedia.org/wiki/Computer_printerhttp://en.wikipedia.org/wiki/Portable_media_playerhttp://en.wikipedia.org/wiki/USB_flash_drivehttp://en.wikipedia.org/wiki/External_hard_drivehttp://en.wikipedia.org/wiki/External_hard_drivehttp://en.wikipedia.org/wiki/Personal_computerhttp://en.wikipedia.org/wiki/Smartphoneshttp://en.wikipedia.org/wiki/Personal_digital_assistanthttp://en.wikipedia.org/wiki/Serial_cablehttp://en.wikipedia.org/wiki/Ajay_Bhatthttp://en.wikipedia.org/wiki/Serial_porthttp://en.wikipedia.org/wiki/Parallel_porthttp://en.wikipedia.org/wiki/Computer_peripheralhttp://en.wikipedia.org/wiki/Mouse_(computing)http://en.wikipedia.org/wiki/Computer_keyboardhttp://en.wikipedia.org/wiki/Digital_camerahttp://en.wikipedia.org/wiki/Digital_camerahttp://en.wikipedia.org/wiki/Computer_printerhttp://en.wikipedia.org/wiki/Portable_media_playerhttp://en.wikipedia.org/wiki/USB_flash_drivehttp://en.wikipedia.org/wiki/External_hard_drivehttp://en.wikipedia.org/wiki/External_hard_drivehttp://en.wikipedia.org/wiki/Personal_computerhttp://en.wikipedia.org/wiki/Smartphoneshttp://en.wikipedia.org/wiki/Personal_digital_assistant


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video game consoles, and as a power cord between a device and an AC

adapter plugged into a wall plug for charging. As of 2008, there are about

2 billion USB devices sold per year, and approximately 6 billion totals soldto date.

CPU socket or CPU slot:-

A CPU socket or CPU slot is an electrical component that attaches to a

printed circuit board (PCB) and is designed to house a microprocessor. It

is a special type of integrated circuit socket designed for very high pin

counts. A CPU socket provides many functions, including providing a

physical structure to support the CPU, providing support for a heat sink,

facilitating replacement (as well as reducing cost) and most importantly

forming an electrical interface both with the CPU and the PCB. CPU

sockets can most often be found in most desktop and server computers

(laptops typically use surface mount CPUs), particularly those based on

the Intelx86 architecture on the motherboard.

ATX:-

ATX (Advanced Technology Extended) is a computer form factor

specification developed by Intel in 1995 to improve on previous de-facto

standards like the AT form factor. It was the first big change in computer

case, motherboard, and power supply design in many years, improvingstandardization and interchangeability of parts. The specification defines
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the key mechanical dimensions, mounting point, I/O panel, power and

connector interfaces between a computer case, a motherboard, and a

power supply. With the improvements it offered, including lower costs,ATX overtook AT completely as the default form factor for new systems

within a few years.

ATX addressed many of the AT form factor's annoyances that hadfrustrated system builders. Other standards for smaller boards (including

microATX, FlexATX and mini-ITX) usually keep the basic rear layout but

reduce the size of the board and the number of expansion slot positions.

In 2003, Intel announced the BTX standard, intended as a replacement for

ATX. As of 2009, the ATX form factor remains a standard for do-it-

yourselfers; BTX has however made inroads into pre-made systems.

DIMM SOCKETS:-
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DIMM sockets are where the computer's RAM, (or Random Access

Memory), is installed. DIMM stands for Dual Inline Memory Module. The

reason it is called "Dual" is because both sides of the memory modulehave completely separate connections from the other side of the module.

CHIPSET:-

The term chipsetis commonly used to refer to a set of specialized chips

on a computer's motherboard or an expansion card. In personal

computers the first chipset for the IBM PC AT was the NEAT chipset by

Chips and Technologies for the Intel 80286 CPU.

A chipset is usually designed to work with a

specific family of microprocessors. Because it controls communications

between the processor and external devices, the chipset plays a crucial

role in determining system performance.

ISA SLOT:-
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Industry Standard Architecture (in practice almost always shortened

to ISA) was a computer bus standard for IBM compatible computers.

It is designed to connect peripheral cards to the

motherboard, ISA allows for bus mastering although only the first 16 MBof main memory are available for direct access. The 8-bit bus ran at 4.77

MHz (the clock speed of the IBM PC and IBM PC/XT's 8088 CPU), while the

16-bit bus operated at 6 or 8 MHz (because the 80286 CPUs in IBM PC/AT

computers ran at 6 MHz in early models and 8 MHz in later models.) IBM

RT/PC also used the 16-bit bus.

CPU:-

The simplest of terms, its your computers brain. The processor tells your computer what to

do and when to do it, it decides which tasks are more important and prioritizes them to your

computers needs.
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There is and have been many processors on the market, running at many different speeds.

The speed is measured in Megahertz or MHz A single MHz is a calculation of 1 million

cycles per second (or computer instructions), so if you have a processor running at 2000

MHz, then your computer is running at 2000,000,000 cycles per second, which in more basic

terms is the amount of instructions your computer can carry out. Another important

abbreviation is Gigahertz or GHz. A single GHz or 1 GHz is the same as 1000 MHz. Sounds

a bit confusing, so here is a simple conversion:

1000 MHz (Megahertz) = 1GHz (Gigahertz) = 1000,000,000 Cycles per second (or computer

instructions).

Now you can see why they abbreviate it, could you imagine going to a PC store and asking

for a one thousand million cycle PC please. A bit of a mouth full isnt it?

So when buying a new computer always looks for fastest you can afford. The fastest on the

market at the time of writing this article is 3.8 GHz (3800 MHz). Remember though that it is

not necessary to purchase such a fast processor, balance your needs, do you really need top of

the range? Especially when the difference says between a 3.5 GHz (3500 MHz) and a 3.8

GHz (3800 MHz) processor will be barely noticed (if noticed at all) by you, while the price

difference is around 100. With the money you save you could get a nice printer and scanner

package.

Now that we have covered the speeds, there is one more important subject to cover. Whichprocessor? There are 3 competitors at present, the AMD Athlon, Intel Pentium and the Intel

Celeron. They come in many guises, but basically the more cores they have and the higher

the speed means better and faster.

Processors now come as dual core, triple core and quad core. These processors are the

equivalent of running two CPUs (Dual core), three CPU's (Triple core) or four (Quad core).


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In the past Intel Pentium the best and most expensive of them all, and remains today one of

the most popular on the market. In laymans terms it is/was the designer processor, although

AMD have some superb if not better releases and equally highly priced and advanced

products. It would be hard to say which is best as they are direct competitors.

Lastly there is the Intel Celeron; this processor is a budget version of the Intel

Pentium 4, the processor you find in most budget computers. If the purse is tight, and youneed a computer, then this is your port of call. You will find many sub 400 computers fitted

with this processor.


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RAM:-

Random Access Memory (RAM) provides space for your computer to read and write data to be accessed by the CPU (central processing unit). When people refer to a computer's

memory, they usually mean its

If you add more RAM to your computer, you reduce the number of times your CPU must

read data from your hard disk. This usually allows your computer to work considerably

faster, as RAM is many times faster than a hard disk.

RAM is volatile, so data stored in RAM stays there only as long as your computer is running.

As soon as you turn the computer off, the data stored in RAM disappears.

When you turn your computer on again, your computer's boot firmware (called BIOS on aPC) uses instructions stored semi-permanently in ROM chips to read your operating system

and related files from the disk and load them back into RAM.

SDR, DDR, DDR2, and DDR3 RAM

Several types of RAM are used in modern computers. Before 2002, most computers used

single data rate (SDR) RAM. Most computers made since then use either double data rate

(DDR),

DDR2, or DDR3 RAM. DDR2 is able to achieve faster transfer rates to prevent limitation ofyour CPU's performance, and DDR3 technology takes these advancements even further.


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Note that these RAM technologies are not interchangeable. One type of RAM will notfunction if installed with another type, and physical differences in the RAM modules prevent

them from even being inserted in the same computer.

HARD DISK DRIVE (HDD):-

A hard disk drive (hard disk, hard drive, HDD) is anon-volatile storage device for digital

data. It features one or more rotating rigid platterson a motor-driven spindle within a metal

case. Data is encoded magnetically by read/write heads that float on a cushion of air above

the platters, with modern storage capacity measured ingigabytes and terabytes.

Hard disk manufacturers quote disk capacity in SI-standard powers of 1000, wherein a

terabyte is 1000 gigabytes and a gigabyte is 1000 megabytes. With file systems that measure

capacity in powers of 1024, available space appears somewhat less than advertised capacity.

The first HDD was invented by IBM in 1956. They have fallen in size and cost over the

years, displacingfloppy disks in the late 1980s as the preferred long-term storage mechanism

for personal computers. Most desktop systems today have standardized on the 3.5" form

factor, and though mobile systems most often use 2.5" drives, both sizes operate on similar

high-speed serialinterfaces.
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Raw unformatted capacity of a hard disk drive is usually quoted with SI prefixes (metric

system prefixes), incrementing by powers of 1000; today that usually means gigabytes (GB)

and terabytes (TB). This is conventional for data speeds and memory sizes which are not

inherently manufactured in power of two sizes, as RAM and Flash memory are. Hard disks

by contrast have no inherent binary size as capacity is determined by number of heads, tracks

and sectors.

This can cause some confusion because some operating systems may report the formatted

capacity of a hard drive usingbinary prefixunits which increment by powers of 1024.

A one terabyte (1 TB) disk drive would be expected to hold around 1 trillion bytes

(1,000,000,000,000) or 1000 GB; and indeed most 1 TB hard drives will contain slightly

more than this number. However some operating system utilities would report this as around

931 GB or 953,674 MB. (The actual number for a formatted capacity will be somewhat

smaller still, depending on the file system). Following are the several ways of reporting
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CD-ROM:-

CD-ROM (an acronym of "compact disc read-only memory") is a pre-pressed compact disc

that contains data accessible to, but not writable by, a computer for data storage and music

playback, the 1985 Yellow Book standard developed by Sony and Philips adapted the

format to hold any form ofbinary data.

CD-ROMs are popularly used to distribute computer software, including games and

multimedia applications, though any data can be stored (up to the capacity limit of a disc).

Some CDs hold both computer data and audio with the latter capable of being played on a

CD player, while data (such as software or digital video) is only usable on a computer (such

asISO 9660 format PC CD-ROMs). These are called enhanced CDs .

Although many people use lowercase letters in this acronym, proper presentation is in all

capital letters with a hyphen between CD and ROM. It was also suggested by some,

especially soon after the technology was first released, that CD-ROM was an acronym for

"Compact Disc read-only-media", or that it was a more "correct" definition. This was not the

intention of the original team who developed the CD-ROM, and common acceptance of the

"memory" definition is now almost universal. This is probably in no small part due to the

widespread use of other "ROM" acronyms such as Flash-ROMs and EEPROMs where

"memory" is usually the correr

SI prefixes (hard drive)equivalent Binary prefixes(OS) equivalent

1 TB (Terabyte) 1 * 10004 B 0.9095 TB (Terabyte) 0.9095 * 10244 B

1000 GB (Gigabyte) 1000 * 10003 B 931.3 GB (Gigabyte) 931.3 * 10243 B

1,000,000 MB (Megabyte) 1,000,000 * 10002 B953,674.3 MB

(Megabyte)

953,674.3 * 10242

B

1,000,000,000 KB

(Kilobyte)

1,000,000,000 * 1000

B

976,562,500 KB

(Kilobyte)

976,562,500 * 1024

B

1,000,000,000,000 B (byte)
http://en.wikipedia.org/wiki/Acronym_and_initialismhttp://en.wikipedia.org/wiki/Read-only_memoryhttp://en.wikipedia.org/wiki/Compact_dischttp://en.wikipedia.org/wiki/Computer_data_storagehttp://en.wikipedia.org/wiki/Yellow_Book_(CD_standard)http://en.wikipedia.org/wiki/Yellow_Book_(CD_standard)http://en.wikipedia.org/wiki/Sonyhttp://en.wikipedia.org/wiki/Philipshttp://en.wikipedia.org/wiki/Binary_filehttp://en.wikipedia.org/wiki/Softwarehttp://en.wikipedia.org/wiki/Softwarehttp://en.wikipedia.org/wiki/Compact_Disc_Playerhttp://en.wikipedia.org/wiki/ISO_9660http://en.wikipedia.org/wiki/ISO_9660http://en.wikipedia.org/wiki/Enhanced_CDhttp://en.wikipedia.org/wiki/Read-only_memoryhttp://en.wikipedia.org/wiki/SI_prefixhttp://en.wikipedia.org/wiki/Binary_prefixeshttp://en.wikipedia.org/wiki/Binary_prefixeshttp://en.wikipedia.org/wiki/SI_prefixhttp://en.wikipedia.org/wiki/Binary_prefixeshttp://en.wikipedia.org/wiki/Acronym_and_initialismhttp://en.wikipedia.org/wiki/Read-only_memoryhttp://en.wikipedia.org/wiki/Compact_dischttp://en.wikipedia.org/wiki/Computer_data_storagehttp://en.wikipedia.org/wiki/Yellow_Book_(CD_standard)http://en.wikipedia.org/wiki/Sonyhttp://en.wikipedia.org/wiki/Philipshttp://en.wikipedia.org/wiki/Binary_filehttp://en.wikipedia.org/wiki/Softwarehttp://en.wikipedia.org/wiki/Compact_Disc_Playerhttp://en.wikipedia.org/wiki/ISO_9660http://en.wikipedia.org/wiki/Enhanced_CDhttp://en.wikipedia.org/wiki/Read-only_memory


15/16

At the time of the technology's introduction it had more capacity than computer hard drives

common at the time. The reverse is now true, with hard drives far exceeding CDs, DVDsand

Blue-ray, though some experimental descendants of it such as HVDs may have more space

and faster data rates than today's biggest hard drive

CD-ROM drives
http://en.wikipedia.org/wiki/Hard_drivehttp://en.wikipedia.org/wiki/DVDhttp://en.wikipedia.org/wiki/DVDhttp://en.wikipedia.org/wiki/Blu-rayhttp://en.wikipedia.org/wiki/Holographic_versatile_dischttp://en.wikipedia.org/wiki/Holographic_versatile_dischttp://en.wikipedia.org/wiki/Hard_drivehttp://en.wikipedia.org/wiki/DVDhttp://en.wikipedia.org/wiki/Blu-rayhttp://en.wikipedia.org/wiki/Holographic_versatile_disc


16/16

CD-ROM discs are read using CD-ROM drives. A CD-ROM drive may be connected to the

computer via an IDE (ATA), SCSI, S-ATA, Firewire, orUSB interface or a proprietary

interface, such as thePanasonic CD interface. Virtually all modern CD-ROM drives can alsoplay audio CDs as well as Video CDs and other data standards when used in conjunction

with the right software.

CD-ROM drive can sometimes be a misnomer for newer drives that are capable for reading

and burning DVDs, the CD's successor which is now the standard optical disc drive.

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http://en.wikipedia.org/wiki/Advanced_Technology_Attachmenthttp://en.wikipedia.org/wiki/SCSIhttp://en.wikipedia.org/wiki/S-ATAhttp://en.wikipedia.org/wiki/Firewirehttp://en.wikipedia.org/wiki/USBhttp://en.wikipedia.org/wiki/USBhttp://en.wikipedia.org/wiki/Panasonic_CD_interfacehttp://en.wikipedia.org/wiki/Panasonic_CD_interfacehttp://en.wikipedia.org/wiki/Panasonic_CD_interfacehttp://en.wikipedia.org/wiki/Red_Book_(audio_CD_standard)http://en.wikipedia.org/wiki/Video_CDhttp://en.wikipedia.org/wiki/Video_CDhttp://en.wikipedia.org/wiki/Advanced_Technology_Attachmenthttp://en.wikipedia.org/wiki/SCSIhttp://en.wikipedia.org/wiki/S-ATAhttp://en.wikipedia.org/wiki/Firewirehttp://en.wikipedia.org/wiki/USBhttp://en.wikipedia.org/wiki/Panasonic_CD_interfacehttp://en.wikipedia.org/wiki/Red_Book_(audio_CD_standard)http://en.wikipedia.org/wiki/Video_CD

the main circuit board of a microcomputer

Documents