The Heart and Soul of a

ComputerBy Andrew Williams

Introduction The Computer is a very essential item in everyday

life. It allows you surf the internet, play games, create blogs, inter-web communication and much, much more.

But how does a computer actually work? In this presentation, I shall show you all the internal components of a computer to show how it ticks!?!?!?

Contents•The CPU ----------------------------------------------------Page 4•RAM (Random Access Memory) ---------------------Page 5•ROM (Read Only Memory) ----------------------------Page 6•Virtual Memory/Cache Memory/Flash Memory ---Page 7•PCI & PCIe Adapter Cards -----------------------------Page 8•ATA Types -------------------------------------------------Page 9 •SCSI & SSD ----------------------------------------------Page 10

The CPUThe CPU is like the brain of the computer as it commands the whole computer and executes specific instructions. As you might guess it gets very hot and therefore has a heat sink to try to cool down the CPU. Sometimes, it might even have an extra one (Works so hard for so little pay!) CPU SIZE is measured in bits (Bytes) and CPU SPEED is measured in GHz (Gigahertz). These can be easy to mix up but they are different things!

Sometimes, the CPU is incompatible with the rest of the motherboard. There can be many petty problems but a very common problem is that the CPU has inadequate wattage as the other motherboard components run on a lower wattage

RAM (Random Access Memory) RAM (Random Access Memory) is a type of volatile memory (normally in

the form of integrated circuits) that allows data to be withdrawn randomly.

DRAM (Dynamic RAM) is similar to RAM but data is stored in capacitors (an electronic component) within each integrated circuit (each chip). The design of a DRAM is simple as it does not need a lot of components per bit of memory although DRAM is still volatile (it loses data if powered down)

SRAM (Static RAM) works differently to DRAM as the design is complicated because lots of components are required per bit of memory. SRAM also keeps residual data after removal of data however it is still volatile (it still loses data if powered down)

ROM (Read Only Memory) ROM (Read only memory) is a type of memory that is ‘read only’, so you cannot modify or

change it without the greatest of difficulties. This memory is also non-volatile compared to RAM and its relatives meaning that memory is not lost after powering down.

EPROM (Erasable Programmable ROM) is a type of memory similar to ROM but Removing and Adding data is possible via UV light (Ultraviolet light). EPROM is also easily distinguished from the rest as it has a fused quartz window for visibility to the chip to allow UV exposure

EEPROM (Electrically Erasable Programmable ROM) is a type of memory which is an identical copy of EPROM except instead to being modified via UV light, it is modified via Electricity

(Both EPROM and EEPROM are non-volatile)

Virtual Memory – Cache Memory – Flash Memory

Virtual Memory is a way of extending RAM memory where a portion of the hard drive is partitioned (separated) and then set aside and then combines for the total memory (a 4gb RAM and a 1GB ‘spare partition’, the system has a total memory of 5GB). This allows memory to be effectively swapped as RAM data can go to the ‘spare partition’ and back again, although excessive use can lead to reduced performance.

Cache memory is a smaller type of memory, used by the CPU (Central Processing Unit) that helps reduce access time to memory if the memory type is ‘cached’.

Flash memory is, in essence the same as EEPROM (Electronically erasable programmable ROM) but an updated version.

PCI & PCIe adapter cards A PCI (Peripheral Component Interconnect) adapter card connects various

devices to a computers central processor. It does this by establishing a bus with all connected devices for communication

A PCIe (PCI express) is a similar adapter card to a PCI adapter card however is considered a replacement as contains many improvements such as speed

ATA Types SATA (Serial ATA or Serial Advanced Technology Attachment) is a connector for

connecting Host Bus Adapters (connections from the computer to other storage and network devices) to mass storage devices. This was made to replace the older PATA (See Below)

PATA (Parallel ATA) is technically the same as SATA but older and much slower* and incompatible with SATA connectors . It is also easily distinguished from SATA as PATA uses a ribbon cable whereas SATA uses a standard cable

(*PATA transfer speeds go up to 133 Mbps whereas SATA transfer speeds can go up to 600 Mbps!)

SCSI and SSD SCSI (Small Computer System Interface) is a set of standards that enables

physical connection (and data transfer) between the hub (e.g. the computer) and a peripheral. The most common use for the SCSI standard are for Hard drive) and Tape drives but can be used for a whole range of devices

SSD (Solid State Drive or Solid State Disk) is a type of data storage that uses solid state memory (memory that does not have moving parts) to store memory in a non-volatile (See Page 6) memory.