Author: Technical Manager
Ver. 1.0
Prabal Mahendra
Date 29.09.14


Floppy disk drive

Hard disk drive

Optical disc drive

Motherboard

Northbridge

Southbridge

Power supply

Case

Cooling system

CPU

RAM

Display devices

Adapter card

Ports

Cables
The Floppy Disk Drive (FDD) magnetically reads and writes information into floppy disks. Floppy disks are a form of removable storage. The FDD is mounted inside the computer unit and is only removed from the system for repairs or upgrades.
The standard size for modern day floppy disks is a 3 ½-inch disk with a hard plastic exterior shell that protects the thin, flexible disk inside. Standard Floppy Disks hold 1.44 MB of data, which is useful for simple files, such as Microsoft Word documents, but not very effective for graphical content. With the introduction of the USB Removable Drive, the Floppy Disk Drive has somewhat disappeared from newer computer systems.
The floppy drives are used to read the floppy disks.
When installing a floppy drive, it is connected using a floppy drive cable, and a 4-pin berg or molex connector (depending on the drive). An external drive uses its own connection (e.g. USB).
In MS-Dos (and related operating systems), the drive letter assigned to the drive depends on the physical connection selected on the FDD cable. If it is connected to the end of the cable, it is drive A. If it is connected to the middle, it is drive B. Up to two devices may be connected. While some FDD connectors may include two connectors at the end and at middle, only one connector in the pair may be used to operate a drive.
5¼-inch drive
3½ connection
3½-inch drive Floppy disk drive cable, supporting ether a 5¼ or

From left to right, 8-inch floppy, 5¼-inch floppy, and 3½-inch floppy
The floppy disks are legacy storage mediums that contain a small amount of data. Despite the larger size, the 8-inch and 5.25-inch disks store less data than the 3.5-inch disk, due to less efficient manufacturing and design.
The disks themselves have three major components. The outer envelope provides protection against some external hazards, such as dust (although the older floppies are stored in an additional envelope.) On the inside of the envelope is a cloth to reduce turning friction, and is placed on both sides of the magnetic film used to store the data. The 3½-inch disk also has a sliding metal tab that provides some additional protection.
Write-protect notch for the 5¼-inch floppy
Floppy disks are given an ability to protect against accidental write operations. With a 3½-inch floppy, there is a slidable tab on the back of the disk.
A hard disk drive (HDD), commonly referred to as a hard drive, or hard disk, is a non-volatile storage device which stores digitally encoded data on rapidly rotating platters with magnetic surfaces. Strictly speaking, "drive" refers to a device distinct from its medium, such as a tape drive and its tape, or a floppy disk drive and its floppy disk. Early HDDs had removable media; however, an HDD today is typically a sealed unit (except for a filtered vent hole to equalize air pressure) with fixed media.
There are four main connection types for HDDs. These are:
 PATA - parallel ATA. (previously known as IDE or EIDE).


SATA - serial ATA.
 SCSI - small computer system interface.
External - hard drives that connect to an external port on the system.
A parallel ATA ribbon cable

The parallel ATA (PATA) is a keyed 40-pin connection commonly in a form of a ribbon cable, with the first pin being marked by a red wire. Most cables give two connections for two potential hard drives. The later standard of PATA allowed for a total of 80 connections (2 per pin) for a faster transfer rate.
Hard drives connected by this system need to be set to either a Master or Slave using a removable jumper. In some cases, you may need to set the jumper to "Cable select" if the cable is designed in that fashion.
Mainboards normally have two PATA connections available, and support two devices on each connection. Expansion cards are available to allow additional hard drives within a computer.
Parallel ATA originally supported 16MB/s. Later versions of ATA increased the speed to 33, 66, 100, and 133MB/s.
SATA and its port
Serial ATA hard drives use a small connector. Unlike Parallel ATA, only one hard drive per port is allowed.
Despite only having a few pins, Serial ATA is much faster than the predessor. It allows data transfer starting at 1.5 Gbit/s
(192MB/s), and can be as high as 6Gbit/s.
SCSI, or Small Computer System Interface, is a standard for attaching multiple devices onto a single connection chain. It normally allows 7 or 15 devices depending on the standard (not counting the SCSI controller itself.)
SCSI connection chains must be terminated - otherwise you will have undesirable interference preventing the devices from working.

There are hard drives that connect to an external port on the computer, either due to their design, or because they are mounted in an external hard drive. The common connection types include Firewire and USB - both of these connections are described in more detail in the ports chapter.
An optical disk drive is a storage medium from which data is read and to which it is written by lasers. Optical disks can store much more data, up to 6 gigabytes (6 billion bytes), than most portable magnetic media, such as floppy disks.
There are several basic types of optical disks:
1.
CD-ROM : Like audio CDs, CD-ROMs come with data already encoded onto them. The data is permanent and can be read any number of times, but CD-ROMs cannot be modified.
2.
WORM : Stands for write-once, read -many. With a WORM disk drive, you can write data onto a
WORM disk, but only once. After that, the WORM disk behaves just like a CD-ROM.
3.
CD-R: Stands for Compact-Disc Recorable, which can be written to once (aside from multisession writing).
4.
CD-RW: Stands for Compact-Disc Rewriteable, which behave similar to CD-R but can be erased to create a new blank disk.
5.
DVD: A Digital Versatile Disc, which allows storing up to 4.7 GB. May appear as Double-Layer to contain 8.5 GB, and can even be double-sided to double the capacity once again.
6.
DVD-R: A recorable version of DVDs.
7.
DVD-RW: A rewritable version of DVDs.
These three technologies are not compatible with one another; each requires a different type of disk drive and disk. Even within one category, there are many competing formats, although CD-ROMs are relatively standardized.
A motherboard is the central or primary printed circuit board (PCB) making up a complex electronic system, such as a modern computer or laptop. It is also known as a mainboard, baseboard, system board, planar board, or, on Apple computers, a logic board, and is sometimes abbreviated casually as mobo.[1]
Most motherboards produced today are designed for so-called IBM-compatible computers, which held over 96% of the global personal computer market in 2005.[2] Motherboards for IBM-compatible computers are specifically covered in the PC motherboard article.
A motherboard, like a backplane, provides the electrical connections by which the other components of the system communicate, but unlike a backplane also contains the central processing unit and other subsystems such as real time clock, and some peripheral interfaces.
A typical desktop computer is built with the microprocessor, main memory, and other essential components on the motherboard.
Other components such as external storage, controllers for video display and sound, and peripheral devices are typically attached to the motherboard via edge connectors and cables, although in modern computers it is increasingly common to integrate these
"peripherals" into the motherboard.
All of the basic circuitry and components required for a computer to function are onboard the motherboard or are connected with a cable. The most important component on a motherboard is the chipset. It often consists of two components or chips known as the
Northbridge and Southbridge, though they may also be integrated into a single component. These chips determine, to an extent, the features and capabilities of the motherboard.
Northbridge
In Northbridge and Southbridge chipset architecture designs, the Northbridge is the chip, or collection of chips, that connect a
Central Processing Unit (CPU) to memory, the Peripheral Component Interconnect (PCI) bus, Level 2 (L2) cache and Accelerated
Graphics Port (AGP) activities. The Northbridge chip communicates with the CPU through the Front-Side Bus (FSB).

The Northbridge chip is one of two chips that control the functions of the chipset. The Northbridge can consist of more than one discrete chip unlike the Southbridge which is typically only one discrete chip.
Southbridge
Southbridge is a chipset that manages the basic forms of input/output ( I/O ) such as Universal Serial Bus ( USB ), serial , audio,
Integrated Drive Electronics ( IDE ), and Industry Standard Architecture ( ISA ) I/O in a computer. Southbridge is one of two chipsets identified as Northbridge /Southbridge. The Northbridge chip/chip set controls the processor, memory, Peripheral
Component Interconnect ( PCI ) bus , Level 2 cache , and all Accelerated Graphics Port ( AGP ) activities. Southbridge consists of one chip, which sits on Northbridge's PCI bus.
 What is a power supply
 Types of PSU – ATX, Versions of ATX, TFX, Micro ATX


High Power PSU (used in Gaming systems and powerful computers)
PSU for Servers





Redundant PSU
Hot Swap PSU (used in Servers)
Cable Management PSU
Popular brands of PSU in Australia and the world– Antec, ACBel, Corsair,…
PSU Features:
Active PFC
Low Noise
Fans – Sleeve, Ball Bearing etc. – how they affect
i) CPU Fans
OEM CPU Coolers come as standard with retail boxed CPU both Intel and AMD
Third Party CPU Coolers-
Popular High Performance Brands:
Antec, Coolermaster, Zalman, Corsair, Noctua, Prolimatech, Scythe, Thermalright, Zerotherm etc.
(see website: http://www.gocomp.com.au/index.php?cpath=product&catpath=0_185_201)
Discussion:
How to install Heat Sink on CPU
Importance of Heat Sink Compound (also called thermal paste)
How to uninstall a CPU fan and reinstall if required ii) CPU Water Cooling
Explain bit about these. Popular brands are Thermaltake.
Intel 38 degree Case specs – what is this, describe

Brands of popular case Fans and difference between them
Sizes: Most popular: 80mm, 120mm
(See website: http://www.gocomp.com.au/index.php?cpath=product&catpath=0_185_202)
Airflow technique in case cooling
This CPU uses numerous pins to connect to the motherboard.
The CPU (Central Processing Unit) is the 'brain' of the computer.
It's typically a square ceramic package plugged into the motherboard, with a large heat sink on top (and often a fan on top of that).
All instructions the computer will process are processed by the CPU. There are many "CPU architectures", each of which has its own characteristics and tradeoffs. The dominant CPU architectures used in personal computing are x86 and PowerPC. x86 is easily the most popular processor for this class of machine (the dominant manufacturers of x86 CPUs are Intel and AMD).
Most CPUs divide the tasks of interpreting and carrying out the instructions between:
1.
A control unit that directs program flow and
2.
One or more execution units that perform operations on data.
Almost always, a CPU includes a collection of registers to hold operands and intermediate results.
When every part of a CPU sits on a single physical integrated circuit, one calls it a microprocessor. Practically all CPUs manufactured today class as microprocessors.
The term "CPU" often refers—imprecisely—to other centrally important parts of a computer, such as caches and I/O controllers, especially when those functions exist on the same microprocessor chip as the CPU. With the arrival of multi-core chips, the term
CPU can either mean the physical chip (see the picture) mounted on the motherboard, or it can mean the core within the chip.
Manufacturers of desktop computers occasionally erroneously describe the entire personal computer (the system unit or sometimes white box , including the computer case and the computer hardware it contains) as the CPU. Rather, the CPU, as a functional unit, consists of that part of the computer which actually executes the instructions (add, subtract, shift, fetch, etc.).
CPUs contain a small amount of static RAM (SRAM) called a cache. Some processors have two or three levels of cache, containing as much as several megabytes of memory.
There are many types of CPU's.Many processor architectures can also be characterized by their CPU design, like register size.
Today most desktop computers and laser printers have 32-bit processors. Some 64-bit processors are rapidly becoming more widespread. Smaller devices like mobile phones, PDAs, or portable video game devices may have 16 or 8-bit processors.
Embedded systems such as microwave ovens, calculators, computer keyboards, and infrared remote controls typically have 8-bit or 4-bit processors.
Socket Types

D) LGA 775
E) LGA1155/1156
F) LGA 1366
G) Xeon
Socket 754
AMD Sempron/Athlon 64 CPUs - single memory channel
Socket 939
AMD Athlon 64 CPUs - Dual channel memory - chip has 2 on-board memory controllers that work in parallel
Socket 940
AMD Opteron CPUs - Primarily for servers, has dual channel memory with error correction, hence the extra pin
AM2 AM2+
Newest socket from AMD (7-4-06) - Supports DDR2 Memory - Very similar to the Socket 940 AM2+ socket supports AMD
Quad Core processor, looks the same visually as AM2
AM3
FM1
The chipset commonly is divided into two devices, the northbridge, and the southbridge. The northbridge is usually the more powerful of the two, and is the closer chip to the physical CPU.
The northbridge, essentially has a few primary functions. Grabbing/Addressing memory from the RAM, and deploying the contents over the data bus for the CPU to read. The northbridge also controls how much ram can be installed into the system. The other functions is allowing the southbridge and its parts, and the AGP slot to communicate with the CPU. In essence the northbridge acts like sort of a receptionist for the cpu, channeling communication from other parts to communicate directly to the
CPU. Today, now that the AGP slot is being phased out, and memory controlers are being implemented directly into CPU cores, the northbridge is becoming marginalized if not completely left out of current designs. One example would be the AMD64 in which the memory functions of the northbridge is now in the CPU core, and there is only a southbridge in the chipset.
The southbridge is another chip in the total chipset. Usually the same size as the northbridge, but further away from the CPU
(usually near the BIOS), it controls the communication between various peripheral components. A list of what a common southbridge would control would be, IDE controlers, USB ports, PCI slots, and so on. The southbridge also has many other features, but it depends on the features the board has, since most are embedded into the southbridge.
Types of RAM
SRAM
SRAM -- Static Random Access Memory. From the book bag analogy SRAM would mostly relate to a small notepad. One of the major features of SRAM is that it never has to be refreshed so data never changes; also SRAM is faster than DRAM. The major drawback however is price, although chip prices have continued to fall, SRAM is still more expensive than DRAM. The most common area SRAM is implemented in the CPU cache where memory doesn’t need to be refreshed often and speed is a factor, and where small quantities are economical. Classic Pentiums and 486 CPUs had SRAM on the motherboard. No memory addresses are assigned in this memory. The 'S' in SDRAM does not mean Static, but Synchronous.

DRAM
DRAM -- Dynamic Random Access Memory. In the book bag analogy, DRAM would be scratch paper. DRAM is the primary memory used in computers today. The advantage of DRAM is that it is very dense, more and more memory is being crammed into chips every day, and getting cheaper at the same time. The main disadvantage is that it is slower, and has to be refreshed often.
Today the most common found ram is SDRAM, Synchronous Dynamic Random Access Memory. The now more common variant of SDRAM is DDR which allows two times the data to be moved in a single cycle, and has dual channel ability. A less common, and now rarely used type of DRAM is RDRAM created by Rambus. Although faster than DDR, the industry decided to use DDR due to licensing issues and overall cost.
VRAM
Video RAM memory is not used as much today as it once was due to the fact that most PC comes with integrated graphics that uses system ram to store display information. Most high-end video graphics cards contain VRAM. VRAM deals with only the display of the bitmap graphics. It can be read and manipulated at the same time, making it faster than ordinary RAM. Because of these enhancements, they are extremely expensive and thus most integrated graphics do not come with VRAM.
RAM Form Factors
RAM comes in many forms; the certification test has questions on legacy and current ram form factors. The following list of form factors have been used in the past:
Name Rate
SDRAM (Synchronous Dynamic RAM)
100 MHz - 200 MHz (PC-1600 -> PC3200)
DDR (Double Data Rate SDRAM)
DDR2
DDR3
100 MHz - 266 MHz (PC2-3200 -> PC2-8600)
100 MHz - 200MHz (PC-6400 -> PC3-12800)
Description
Graphics card memory is permanently attached to the graphics card.
Memory Modes
 Real Mode is the main mode that was used in early PCs, it is still used today, during booting on a normal 32-bit pc. When windows starts, protected mode kicks in, and real mode is turned off. Real mode was introduced with the 16-bit 286 processor, in real mode, 1 Megabyte of memory could be addressed at most.
 Protected Mode is another mode that was introduced with the 286, allowing ***, protected mode mostly turned on when the operating system is loaded on the system. Protected mode when introduced was only exploited on windows 3.0 and up, however, other OSes also use protected mode. The main function of this mode is to give the ability to break the 1 MB barrier, and allow more memory to be addressed by the computer. Protected mode has changed sinced its initial introduction on the 286, on the 386 for instance, there was 'standard' and 'enhanced', standard allowed up to 16 bits to be addressed, while enhanced allowed 32 bits to be addressed.
3 Types:
PCI
PCI Express
AGP

Most common cards are PCI. PCI Express and AGP are mainly used for video adapter cards.
Explain the differences and show different types of cards.
To identify look at the slots. That is the only way to distinguish the different types of cards.
Control Bus: The physical connections that carry control information between the CPU and other devices within the computer.
Whereas the data bus carries actual data that is being processed, the control bus carries signals that report the status of various devices. For example, one line of the bus is used to indicate whether the CPU is currently reading from or writing to main memory. (Webopedia.com)
Electrical bus
Bus bar
System Bus
Data bus
Bus Architecture
Industry Standard Architecture (ISA) This architecture was originally used in the IBM PC/XT and PC/AT used for connecting peripheral devices. It has been made obsolete by PCI.
Peripheral Component Interconnect (PCI) Developed by Intel Corporation. It is a standard for local bus. It has a throughput rate of
133MBps.
Accelerated Graphics Port (AGP) A standard for 3-D graphic interfaces. Its first incarnation had a bandwidth of 266MBps with
2x, 4x, and 8x versions later following. The x is how many times 266MBps set bandwidth is (2x would be 533MBps, etc.). AGP ports are still common but are quickly being made obsolete by PCI Express.
Ports on the computer are used to send or receive data. Physical ports are usually found in the back of the system and allow connecting devices to the computer. The most common ports are:
Port name
9-pin Serial
25-pin Serial
Parallel
SCSI
VGA
DVI
Audio
Universal Serial
Bus (USB)
Firewire
Image Description
Small Computer Systems Interface.
Used to connect audio devices, such as speakers, microphones, etc.
An external bus which can support up to 127 peripheral devices daisy chained on a single port. It is quickly replacing serial and parallel ports.