Function of each Major Computer Component

Each different part in a computer has a different task to perform, just as each part in an automobile has a job to do.  Each part works differently in order to get it’s job done.  There are many misconceptions about what parts do what job, and here, we will set out to correct them.  Knowing what function each part has is very rewarding.  If one knows what part does one, they can easily narrow down problems in a computer.

The Processor
“CPU”
The processor is known as the brain of the computer.  In fact, it’s not.  If anything, the computer as a whole serves as a brain.  The processor is just a really fast calculator.  It adds, subtracts, multiplies and divides a multitude of numbers.  There are two parts of the Processor that do the math.  The first  part is called the Integer unit.  It’s job is to take care of the “easy” numbers, like -5, 13, 1/2, etc.  It’s mainly used in business applications, like word processors, spreadsheets,  and the Windows Desktop.  The other half is called the Floating Point Unit.  It’s job is to take care of the really hard numbers, like the square root of 3, pi, “e.”, and logarithms.  This part of the CPU is mainly used in 3D games, to calculate the position of pixels, and images.  For years, Intel’s processor have had the best Floating Point around, but as of late, AMD’s Athlon Processor has stolen the crown away from Intel.  That is why were are seeing the race for 1GHz speed up so dramatically today.

The Hard Drive“HD”The Hard Drive is simply a multitude of metal disks that spin around inside your computer, with heads that move around those disks.  Those heads read and write data to the metallic disks.  The reason for using a Hard drive is because the hard drive is the only part inside a computer that stores data while the computer is off. (Besides removable media of course.)  Your Hard Drive is what stores all of your settings, programs, and the operating system while your computer is off.  The only draw back to the hard drive, is that it is mechanical.  That means it has a tendency to break down every once in a while for no reason, and it is slower than electronic means of data storage.

Random Access Memory“RAM”RAM is easily confused with Hard Drive, because both store data.  The two are actually very different.  The RAM is a chip that holds data, only as electricity flows though it.  It is very fast compared to the Hard Drive, but is also expensive, which is why we don’t use it for our primary data storage.  RAM is used as a interface between the Hard Drive and the Processor.  If the Processor needs some data that’s on the hard drive, the chipset (we’ll get to the chipset later) will retrieve the data from the hard drive and put it into memory, so the processor can access it faster.  If the computer runs out of room in the RAM, it will make a file on your hard drive, called “Virtual RAM.”  “Virtual RAM” is just an extension of real RAM on your Hard Drive.  As said above, the Hard drive is much slower than the RAM, so when the computer gets the data strait from the Hard Drive, your computer will also seem like it freezes, because it will be running so slowly. Once you shut your computer off, there is nothing stored in the RAM, because there is no electricity flowing though it.

Cache“L1,and L2”The Cache is high speed RAM.  It stores commonly used data and instructions from the processor so that it doesn’t have to go to the slower RAM to get it.  This is why the modern day computer is so fast.  Without cache, most processors would be limited in speed by the RAM.  Without it, your computer would be running terribly slow.  The Cache is split up into 2 different Levels.  The first level, L1, ranges in size from 32KB to 128KB.  It is split in half and resides with in the CPU core, next to the Integer and Floating Point Unit.  The first half stores commonly used data, and the second half stores common instructions that the processor carries out on the data.  The second level of cache, called L2, is for data only.  Some L2 Caches are on the motherboard.  Others are on a special cartridge with the CPU.  Newer L2 Caches are in the CPU core, with the L1 cache.

The ChipsetThe chipset is the boss inside the computer.  It controls communication between the components.  The chipset is split up into two basic chips.  The first chip, called the North Bridge, handles communication between the AGP bus, (if it exists), RAM, processor, and the South Bridge of the chipset.  The South Bridge handles all the Input and output of the computer, including the PCI and ISA Bus.  The Processor, Memory, Cache, and Chipset all work together to function as a logical brain.             

                                                                  - http://www.pcmech.com/article/function-of-each-major-computer-component/