Computer Hardware Basic

8/6/2019 Computer Hardware Basic

http://slidepdf.com/reader/full/computer-hardware-basic 1/42

Building A PC System

Anyone needing a new computer faces a tough choice: you can either go for a complete

system, or you can build your own PC. As most complete systems are cheaper than thesum of their parts, when is it really worth it to build your own?

Under the hood of a midrange PC



Imagine you want to build a new PC and want to use a few remnants from your old

system. If you were satisfied with the performance of your CD-ROM drive, hard drive,printer or monitor, then it could be worth it to simply buy the remaining components -

you might not even need a new case.

Hope that this article will reach the individualists among you, i.e., users who knowexactly which processor, motherboard and graphics card they want to install, but who justdon't know how to fit it all together. The third group of users we want to reach are those

people who only want to swap out a component, whether a graphics card or a CPU.

Many are intimidated by hardware. Some people won't even put in a new card on their

own if they can help it. Yet the computer is now a mass-market product that, thankfully,

has also brought about broad standardization.

This article will guide you unerringly through each step of successfully building your

own PC. Of course, this article assumes that you know how to properly handle electronic

components, that you know how to use tools, and, perhaps most importantly, that youtake pleasure in this kind of tinkering. As we are going to introduce a large spectrum of

PC components, users who only want to upgrade individual parts can skip certainsections in this guide.

Standard Components Of A PC System

In our enthusiasm and eagerness to offer a complete do-it-yourself guide, we picked up

the price list at the computer store on the corner, only to feel overwhelmed by the sheer

quantity of parts on offer. If you aren't yet used to buying a PC in individual components,it can't do any harm to draw up a list of everything you need before doing anything else.

That said, a complete PC system requires the following items:



PC case



Motherboard

Processor



CPU cooler

RAM



Hard Drive

Graphics card



CD-ROM or DVD drive

Floppy disk drive, if needed

The following items shouldn't be forgotten:

Monitor

Keyboard

Mouse



These components are necessary to run the new computer, including its operating system

(e.g., Windows, Linux).

Extra Options For Special Applications

Depending on what you'll be using your PC for, you might need the followingcomponents as well; please note, though, that this list is by no means complete:

Application Required components

Internet access Modem, ISDN card, or network card (if using DSL)

Gaming and Music Sound card and loudspeakers

CD recording, archiving CD recorder, ZIP drive

Network Network card (Ethernet)

Digital cameraEither a motherboard with integrated USB, or separate USB

card

Video Editing &Camcorder

Video capture card with IEEE1394/FireWire (i-Link) interface,if possible

Case And Power Supply

Power Supply

The advent of processors breaking the gigahertz barrier has made one thing clear: their

thirst for power is hard to rein in. When buying a case, take a very close look at the built-in power supply. In addition to the classic ATX power supply, it should also feature anauxiliary power connector. More and more motherboards require this plug to cover the

power needs of a Pentium 4 or an Athlon XP. The only time you won't need it is if you're

operating a CPU at 1400 MHz or less.



Classic ATX power supply plug.

Extra current for power-hungry CPUs: ATX12 (left) and P6 connector. (right)

An increasingly familiar sight on motherboards: on the left, the P6 (AUX); and on the right, the classic ATX plug.



An ATX12 socket on the motherboard.

Power Connectors For Drives

Your power supply will depend on how many drives you plan to install. Small cases only

offer three or four connectors. Once you've used up all the available connectors, you'll

have to use a Y junction to turn one plug into two.

One into two: a typical Y junction with large plugs.

This cable also comes with small plugs for connecting floppy drives and the like to a

power supply.



Cases: More Questions For The Salesman

Always make a point of asking about assembly materials: are all the screws, spacers andother accessories included with the case? A small bag of assembly materials is usuallystuck to the inside of the case. Always be wary of cheap offers!

A bag of screws should be inside the empty PC case.

Always make sure you have spacers and mounts to secure the motherboard. A few screws

for the case won't hurt either, as they are generally also used to anchor plug-in boards.

The screws for mounting drives (hard drive, CD-ROM, etc.) have a finer thread. You

need at least four for each drive, but it's always a good idea to have a handful of replacements. By the way, you're barking up the wrong tree if you start looking for these

screws at the hardware store. Go to your local computer store - they won't have to look far for the screws you need, and they're bound to be the right size. If possible, avoid

plugging the monitor directly into the PC power supply - you're better off with a separate

connector. While some power supplies offer an additional plug for a monitor, you'd be

well-advised not to use it for screens larger than 19 inches - the high surge at power-up isa frequent source of booting problems.



Ask about the form factor. This depends on the motherboard. Since almost all new

motherboards conform to the ATX form factor, your case will have to be ATXcompatible. You can still scrounge up AT cases for AT motherboards. A modern ATX

motherboard can be identified by the fact that all the jacks for the keyboard, mouse,

parallel printer, and serial COM port are soldered directly onto the motherboard. We'll

document this in the section on the motherboard.

This And That: Screws, Spacers & Jumpers

Typical case screws are used to screw on the case covers and anchor plug-in cards to the case.



A drive screw's thread is finer and thinner than screws used for the case. The head is smaller, too. This kind of screw is generally usedto affix the drives in the drive bays, and to screw the motherboard to the case.

Spacers are screwed into the backplate for the motherboard.

What Are Jumpers?



Jumpers are short and sweet.

A jumper is nothing more than a metal bridge that connects two contacts. We don't seethe metal, though, because it's covered with plastic. Jumpers are often used to configure

the PC. For instance, you can use them to set the processor speed or change a drive from

a "master" to a "slave." Pictured above is a classic jumper, as used on drives and boards

just about everywhere.

Motherboard Overview



Main components of a motherboard.

The image shows an ASUS motherboard. At the top on the right-hand side are the

interfaces and connectors that stick out of the case at the back of an assembled computer.

This board is designed for AMD Athlon and Duron processors. Socket A, as it's called, is

labeled "CPU socket" in the picture. The expansion slots are to its left. The AGP slot isused exclusively for the graphics card. The PCI slots will hold network cards, ISDN,

sound or video-editing boards. At the bottom left are the panel connectors for the on/ off

button, the hard drive LED, the reset switch, and the operating LED. Take time tofamiliarize yourself with where they're located. By the way, LEDs that don't light up can

generally be fixed by simply turning the plug around. The two IDE connectors (40-pin)

are below in the middle, while the connector for the floppy drive (34-pin FDD connector)is in the left side of the image. We'll describe the cables and drive configurations on the

next page.

Onboard Components



ATX connector panel

Keyboard, mouse, two serial connectors, a parallel port and two USB ports are on the

ATX port panel. Some motherboards, like the one here, feature optional sound and joystick jacks. There are also models that have a monitor connection. That saves a slot

and some money, but you'll have to deactivate the onboard chip if you plan to replace

these cheap onboard modules with a higher-quality expansion card. It's generallyimpossible to run both chips at the same time. Once again, it can either be done in BIOS

or with a jumper. Check your handbook to find out which method to use.

Basic Motherboard Configuration

Many modern motherboards with integrated software configuration no longer require youto do anything prior to assembly. That means that you type your processor parameters

directly in BIOS (Basic Input Output System). Most of the time, you access the BIOSmenu by pressing the DEL key, F2 or F10, shortly after switching on the PC. Check your

handbook to find out which key to use. The latest technology even recognizes the CPU

automatically, a feature that is particularly useful for beginners. But making settingsmanually is still a must for anyone who wants to fine-tune his or her system.

Processor Settings: FSB And Multiplier

The external clock speed is usually referred to as the Front Side Bus (FSB), or systemclock. Typical physical frequencies for system clocks are 100.00 and 133.33MHz. The

actual processor clock is calculated by multiplying the system clock with the multiplier.

For example, a Front Side Bus of 133.33MHz and multiplier of 13 results in a physical

CPU clock speed of 1733MHz. Some manufacturers provide "marketing" figures whenDouble Data Rate (DDR) or quad pumping raises effective bandwidth. Here's an example

of such marketing figures, which have been placed in quotes:

Socket/ Slot Processors System Clock (FSB)

Socket 7AMD K6-2,AMD K6-III,

Intel Pentium MMX

66, 100, 133 MHz

Slot 1 Intel Pentium III, 66, 100, 133 MHz



Intel Celeron

Slot A AMD Athlon (K7) 100 MHz (200 MHz DDR)

Socket 370Intel Pentium III,

Intel Celeron,VIA C3

100, 133 MHz

Socket A

(Socket 462)

AMD Athlon (Thunderbird),

AMD Athlon XP (Palomino),

AMD Athlon XP (Thoroughbred),AMD Duron (Spitfire, Morgan)

100 MHz (200 MHz DDR),

133 MHz (266 MHz DDR)

Socket 423Intel Pentium 4 (Willamette),

Intel Pentium 4 (Northwood)100 MHz (400 MHz quad-pumped)

Socket 478Intel Pentium 4 (Northwood),Intel Celeron (Willamette)

100 MHz (400 MHz quad-pumped),133 MHz / (533 MHz quad-pumped)

AMD also lists a so-called P-Rating, or Number Modeling, for marketing purposes. In

other words, an AMD Athlon XP 2100+ actually only runs at a physical speed of 1733MHz. "2100+" is merely a way of comparing the processor to an equivalent IntelPentium 4. Put plainly, an AMD Athlon XP 2100+ is about as fast as a Pentium 4 2100.

Setting The Clock Speed

There is no automatic software configuration on older boards. That's why it can't hurt toknow the three principles of manual configuration. By the same token, overclockers will

be more likely to make settings by hand. Here are the different ways to set clock speed:

Obsolete: using jumpers, the frequency table is right next to the jumper block.



Multiplier table for older models.

Occasionally found: setting by DIP switch.



Modern: convenient configuration in BIOS.

Determining which of the three methods applies to you will depend on your motherboard.

While the general tendency seems to favor BIOS, you'll still come across a DIP switch

block now and again. The jumper method, on the other hand, is entirely obsolete.

Intel and AMD officially abolished the variable multiplier for their processors some time

ago. They wanted to prevent people from overclocking, say, 1300MHz models to1500MHz. That kind of overclocking would boost performance significantly without

costing a dime. For the tinkerers among us, all that's left for us when trying to eke more

performance out of a processor is a gentle increase of the FSB. All the same, there are a

few tricks for removing the fixed multiplier, at least for AMD processors. Moreinformation on this can be found in the article, Plastic Surgery: Releasing The Athlon XP

To Hit 2000+ . As the motherboard manufacturers are aware of this, they attract more

buyers by offering what is, in fact, a superfluous multiplier. The BIOS screenshot shows

this clearly.

Connecting The Floppy Drives

Floppy drives are in danger of extinction because floppies generally don't hold much

data. Most software is generally installed from CD-ROMs now, anyway. CD burners arevery popular for archiving data. Nevertheless, a floppy drive can still pay off if you work

with old programs or data from time to time.



Floppy connector (34-pin) above, IDE connector(40-pin) for hard drives and CD-ROM below.

It's easy to spot floppy cables. They usually have a "twist" of individual wires, as you can

see in the upper corner of the image. The image shows a color marking on a cable. This isfrequently a red line that marks pin 1. Pin 1 is also printed on the motherboard. Onmodern motherboards, notches and/ or a missing pin in the middle (see picture blow)

prevent the cable from being inserted the wrong way. You still need to watch out when

hooking up older drives or motherboards. The red dotted line at the other end of the cable

should always point in the direction of the power supply. Here, too, there is a reverse-connection protection to keep it from being improperly configured.

Connecting Hard Drives And CD-ROM/DVD

The vast majority of hard drives and CD/DVD drives are based on the IDE (Integrated

Device Electronics) standard. There's also the SCSI standard, which is mostly used forservers or workstations. In comparison to SCSI, IDE is extremely cheap to produce,

which accounts for its higher popularity. There are four subgroups within the IDE class:

UltraDMA/33; UltraDMA/66; UltraDMA/100; and UltraDMA/133. The number at the

end describes its bandwidth. As a rule of thumb, the higher, the better. 133, for example,stands for the maximum data transfer rate of 133 megaBytes per second. DMA is short

for Direct Memory Access. A beginner doesn't necessarily have to know how DMA

works in order to obtain good results.

Two drives can be run on each IDE connector block. Motherboards usually have two IDE

connectors (Primary and Secondary IDE), so that a maximum of four devices can be

connected. Modern motherboards with an additional controller can even offer four IDEconnectors. If you want to connect an IDE to a drive, it is configured as a "Master"

(Single). If, on the other hand, two drives need to be connected, one must be labeled"Master," and the other "Slave." The jumpers are used to connect the contacts, thus

configuring the drive. The connection to the motherboard is made by way of a 40-pin

ribbon cable. It has three plugs - one for the motherboard, and the other two for the twodrives.



Most PC systems have one hard drive and one CD-ROM/DVD drive. CD-ROM burners

are also a type of CD-ROM drive. The following configuration is recommended for IDEdrives:

Primary IDE: hard drive as Master (Single) Primary IDE:

Secondary IDE: CD/DVD drive as Master (Single)

Users who want the full allotment of IDE components should connect the drives as

follows:

Primary IDE: hard drive 1 as Master (Dual)

Primary IDE: hard drive 2 as Slave (Dual)

Secondary IDE: CD/DVD drive 1 as Master (Dual)

Secondary IDE: CD/DVD drive 2 as Slave (Dual)

There's usually a sticker on top of the drive explaining the necessary jumper settings. Or,

you can also find a description in the hard drive manual.

IDE jumper table for a Maxtor hard drive.

Port panel on the hard drive: power supply, jumper blocks, IDE ribbon cable (from left to right).

Connecting the CD and/ or DVD drives is basically the same as with hard drives. The

same rules apply.



CD-ROM port panel: digital audio, analog audio, jumper blocks, IDE cable, power supply (from left to right).

SCSI Drives - The Exception

Although the SCSI (Small Computer Systems Interface) bus system offers greaterflexibility, it's also much more expensive. SCSI is only used for workstations and servers.

Ultra2 or Ultra 160 SCSIs are typical standards. A SCSI ribbon cable has 68 pins. All

SCSI standards have one thing in common: you can run at least seven drives on oneadapter. "Wide" models even allow 14 devices to be operated.

It is important to know how it works. SCSI is an open bus system and allows cablelengths of well over a meter. However, the bus must be closed with a terminal resistor at

each end, so that the signals don't reflect. Termination can mostly be activated by a

jumper on the last device. LVD cables have their terminator as a plug-on module. Theposition of the individual devices on the SCSI cable, by the way, is up to you. The drives

are distinguished by way of so-called SCSI Ids that run from 0 to 7 or 0 to 15. ID7 is

usually the host adapter, 0 or 1 is usually used for the hard drive(s). The rest of the

configuration is up to you. Jumpers are used to define the ID address from 0 to 7. In thefollowing example, the manufacturer has named its SCSI address IDs DAS0 to DAS3.



Description of the SCSI jumper block for auxiliary connectors. DAS0 to DAS3 are the SCSI address bits.

Jumper table for setting addresses.

Connector blocks on an SCSI hard drive: power supply, jumper blocks (auxiliary connector), SCSI ribbon cable (from left to right).

In this example, termination can be activated by bridging pins 9 and 10. This is called

"Enable SE SCSI Terminator" in the picture.

safety Notice: The Destructive Potential Of Electrostatic



Walking across a floor dragging your feet will create friction, which charges us with

energy. Once you stop moving, the soles of your shoes insulate you, but you're stillcarrying around a different voltage potential than your environment. Everyone's felt the

sudden shock from a static spark, which is particularly common with plastic floors and

thick, rubber-soled shoes. This electromagnetic phenomenon can have dangerous

consequences for electronic components. Although the current from a static dischargeisn't very high, the voltage difference may briefly peak at tens of thousands of volts. That

much voltage can easily destroy sensitive components such as memory chips.

The most important thing to do before getting down to work is to ground yourself.

Ideally, you'll have an antistatic armband, as used in industry. But unless you're a realelectronics whiz, you're unlikely to have one. So, try this instead: before you come into

contact any of your PC's components, simply touch something metal (a radiator, the

protective contact on a plug or the PC case). This will ground you properly.

Drawing Up A Plan

Before you start the actual assembly, familiarize yourself with the case and components.

Unpack all the parts and keep them nearby, but not so close that they interfere. Most

cases don't come with instructions, so you should first check which screws and parts go

where, and what each is for - and whether you may have to remove anything from thecase before you can install the drives. Get yourself a proper lamp before starting,

especially if you work at night. The ceiling light in your workroom is usually not bright

enough.

Finally, consider where you want to put each drive. There are only a few rules for drive

placement, but valuable ones to follow when in doubt:

If the PC is under your desk, it makes sense to place the CD-ROM and/or DVDdrive as high up as possible so that you don't have to bend down so far.

Always check to make sure that the ribbon cable is long enough.

Some components get warm or even hot when operating. Always make sure that

there's enough air circulating for the heat to dissipate. That's especially importantfor modern graphics cards and hard drives.

If you're intending to put in two hard drives, make sure that there's enough room

between them. Otherwise, they may overheat, leading to a shortened life span andinstability.

Make sure that neither cables nor other components can get caught in a fan.

All cables must be run so that no air vents or openings are completely blocked.

An Overview Of Steps Involved

First, let's take a look at the various steps to putting together a PC.

Opening the empty case;

Preparing to fit the components;



Fitting the motherboard;

Fitting the RAM, processor, and cooler;

Installing the graphics card and sound card;

Fitting the hard disk and floppy drive;

Installing the floppy and CD-ROM drives;

Connecting the ribbon cables; Powering the drives and motherboard;

Connecting the cables for the case front panel;

Final check.

The above list is intended to be used as a general guide. In practice, you can vary theactual order of assembly to some degree. We use a tower case in our demonstration

because it makes for clearer illustrations. The same assembly principles apply for midi

and mini cases.

The case we use has a slide-out tray for the motherboard and the expansion cards. There

are a variety of case designs on the market, and we've discussed this in depth in an earlierarticle, entitled How To Select The Right Case . Take time to familiarize yourself with

the case before installing any components in order to avoid having to remove some of

them later!

Opening The Empty Case

Empty case with motherboard tray withdrawn.

Our tower case is built to ATX specification and includes a 300-watt power supply. Twoside panels can be individually removed after undoing the screws. Some other cases have

a one-piece outer cover in the shape of an upside down 'U.' No matter how the case is

constructed, you can normally gain access to the interior of the PC-to-be from both sides.



The price of a case is a good indicator of its modularity and build quality. Cheaper cases

often force you to assemble the PC in a specific order, are made of softer and/ or thinnermetal, and may contain sharp edges. Expensive cases provide clever design features, a

more solid construction, better finish, and are often fitted with more capable power

supplies.

When you have opened the case by removing the side panels, you will see whataccessories the case manufacture has supplied. A power cord and screws should always

be included, and you will also often find a set of case feet.

Preparing To Fit The Components

Overview of all components (from left to right and top to bottom): network adapter card; floppy disk drive; CD-ROM drive; sound

card; hard disk; ribbon cable; graphics card; RAM; CPU cooler; and, motherboard.

Let's take another look at the photo. The inclusion of a component from a particular

manufacturer does not imply a recommendation on our part. We use them to illustrate the

installation procedure of similar components. The choice of components is entirely up toyou. You can always find reviews of the latest products on the Tom's Hardware site,

together with articles on the latest developments and product recommendations.

Fitting The Motherboard



Empty tray with six motherboard spacers.

Our case has a slide-out tray, which provides a very elegant way to install themotherboard and all of its components. Cheaper cases will have a mounting plate fixed

permanently to the case. If you have this type, you should first lay the case on its side.

Next, screw in the spacer mounts for fixing the motherboard. The photo shows six

spacers already fitted to the mounting plate. There are usually more holes drilled in the

mounting plate than you actually need. There are standard locations for these holes on themounting plate, which correspond to the holes on the motherboard. How many of these

are actually used depends on the board manufacturer. Cases are normally designed to

accept any motherboard. Compare the available holes with the ones on your motherboard

to determine where to fit the threaded spacers.

Spaced well away from the metal - the motherboard on the mounting plate.



Installing The CPU And Cooler

Lift the lever on the CPU socket.



When the processor is in its socket, push the lever back down.

First, insert the CPU in its socket. To do this, raise the small lever at the side of the

socket. If you examine the CPU from underneath, you will notice that there is a pin

missing at one corner. Match this corner with the corner on the socket where there is a

hole missing. The processor is keyed in this way to make sure it is inserted correctly.Please bear in mind that you should not force the CPU when inserting it! All pins should

slide smoothly into the socket. If you are sure that you have positioned the CPU correctly(using the missing pin as reference), yet are unable to insert the CPU, it is likely that one

of its pins is bent. If this has happened, straighten the pin using tweezers or a screwdriver.

Once you have installed the processor, lock the lever back down.

Don't Forget To Use Thermal Paste Or A Thermal Pad



Applying thermal paste to the processor.

You must apply thermal paste or a thermal pad to the top of the CPU. This will help to

transfer heat from the processor to the cooler. Failure to apply a thermally conductive

medium to the processor can cause it to fail! Unless you use thermal paste, any slight

misalignment of the contact surface of the cooler, or even the presence of tiny specks of dust, will prevent heat from being efficiently transferred away from the processor.

Thermal paste also fills the microscopic valleys in the contact surface of the CPU (known

as the die). Some cooler manufacturers supply thermal paste with their products. If yoursdid not, it is available from most good computer or electronics stores and costs around

two to three dollars.

Mounting The Cooler

A cooler made of copper is recommended, since this material is a very efficient heat

conductor. You should know your processor's socket type when buying a cooler. You

have a choice of two types of cooler - one suitable for both Socket A/462 and Socket 370,or one just for Socket 423 (Pentium 4).



Make sure that the cooler is in the correct position. Here is the cooler about to be connected with the socket.



Clips fix the cooler to the socket. This applies to Socket A/462 (AMD) and Socket 370 (Pentium III and C3).

Fan Power Connection

Plenty of air flow. Here is the power connection for the cooler's fan.

You may have wondered why the connector lead for the fan has three wires. Two of these

carry the power; the third is used for monitoring the speed of the fan. Therefore, theBIOS is always aware of the speed at which the fan is running.

Minor Differences With The Pentium 4 System



Socket 370 (Intel Pentium III or Via C3), Socket A/462, and Socket 7 all use the same

method of mounting the cooler. However, Socket 478-based Pentium 4 systems areslightly different. Intel specifies that motherboard manufacturers should provide a plastic

guide rail to ensure that the cooler is always mounted flat to the surface of the processor.

Also, the cooler is not locked down with clips but with a snap-in system, as shown in the

following pictures.

Pentium 4 motherboards have a socket with 478 pins and a guide for the CPU cooler.



Attaching a Pentium 4 cooler

Installing The RAM

The RAM must be suitable for the motherboard. There are currently three types of RAMavailable: SDRAM, DDR SDRAM and RDRAM. The motherboard's chipset determines

which type of RAM may be used. You will find the specification on the motherboard's

box or in the motherboard manual.



Installing RAM. A notch at the bottom of the memory module ensures that the RAM is fitted correctly. The notch is located in

different places on SDRAM, DDR SDRAM and RDRAM.

DIMM memory modules have a notch underneath that lines up with a key on the memory

slots. Although it is not possible to insert the modules the wrong way, you should line up

the RAM with its slot before installing it. Then, carefully press the module into the slot.Caution is recommended, as too much pressure may damage certain tracks on the

motherboard. It is best to push one side down first, and then the other. The notch will

snap into its key as soon as one side is seated correctly. To make sure it is seatedcorrectly, you can always take the memory module out again. Releasing the clips will pop

the module out of its socket. Then, you can just lift it out.

Passed the first hurdle. Motherboard with processor, cooler and memory.

Graphics, Sound And Network



In place - sound card (left) and graphics card (center) in white PCI slots. There is room for a network card, if required.

Nowadays, graphics cards are usually fitted in the AGP slots provided specifically forthis purpose. These are brown in color, in contrast to the PCI slots, and are generally

located in the center of the motherboard. PCI graphics cards are rarely used. Now, select

a PCI slot for each of your other plug-in cards, including the sound card. Before fitting anexpansion card, remove the appropriate slot insert from the back panel of the case (or of

the motherboard tray). As a rule, you need to undo a screw to do this, although

sometimes convenient plastic clips are used. The insert may also form part of the back

panel.

Choosing a location for a PCI card will not usually be a problem on a simple system. Inour experience, however, selecting an appropriate PCI slot can sometimes be problematic

with some brands of motherboard. For example, IRQs can be reserved twice or even three

times over. Resource conflicts can make it difficult for the operating system and

motherboard to work together properly. This can often be solved by moving theoffending PCI card to another slot or by manually reassigning IRQs. The other reason is

more practical. If you see a large heat sink on a plug-in card, perhaps even with a fan on

top, the chip underneath will be producing a lot of heat that has to be removed. There isonly one reason we did not fit the sound card next to the graphics card: we wanted to

keep some space between the cards in order to prevent heat buildup.

Installing The Hard Disk And Floppy

We assume that you have already configured your hard disk the way you want it - single,master, or slave. The photo below shows the hard disk already fitted. As you can see, we

can look right through the case here. If we had slid the motherboard tray back into

position, it would have been impossible to screw the hard disk in from the left.



At the moment, we still have good access to the hard disk (bottom) and the floppy drive (top). You can see the screws for the drive onthe side.

Use two screws per side on each drive. We would like to touch briefly on the topic of

drive cooling, as it is quite important with the current 7,200 rpm drives. Hard disks

running at 7,200 rpm can quickly reach temperatures in excess of 50°C. You should,therefore, always leave some space above them to prevent heat buildup. The powersupply fan is normally powerful enough to provide adequate air circulation inside the

case.

Installing The CD-ROM Drive

Installing a CD-ROM drive is similar to installing a hard disk. First, check that the jumper configuration is correct.



CD Drive In Drive Cage.

You only get to see the metal below the decorative plastic front panel when installing

your system; the case metal is actually hidden by plastic panels. The entire front section,or at least the part where the drives will be installed, is manufactured from a single, large

piece of metal, in which the drive holes are then punched. For some years now, the CE

norm for cases has specified this kind of metal panel, as only metal can reduceelectromagnetic emissions - the processor usually being the worst offender in this area.

In practice, there are two options. If the metal knockouts are pre-stamped, you have toeither take them out using metal cutters, or knock them out using force. If you have a

high quality computer case, you can remove and replace these metal panels whenever you

like. Check carefully to see if there is an easy way to remove these panels that will reducethe chances of your accidentally damaging one or more of them.

When we have opened up the hole, we can feed the CD-ROM drive in and screw it intoplace. You will need the fine-threaded type screws. Always use four screws. Be careful

not to over-tighten the screws, as excess pressure can put a strain on the case that could

lead to twisting. The faster a drive's rotational speed, the more serious the effect. Tightenthe screws only enough to ensure that the drive is secure. Heat is a consideration with

CD-ROM drives, as it is with disk drives.

Connecting The Ribbon Cables

Your PC should now look similar to the one in our photograph. All key components, such

as the motherboard, processor, RAM, graphics card, sound card, hard disk, CD-ROM andfloppy, have been installed. Now it is time to connect the cables.



PC still without the cables

As you will be aware after reading Part 1, there are two main cable types: the 34-pin

cable for the floppy drive and the 40-pin IDE cable (with 80 wires) for the hard disk andCD-ROM. Cables are always color-coded to show pin 1. Most drives also provide some

kind of identification for pin 1. If you find that this is not the case, just remember that pin

1 is the one next to the power plug.



Ribbon cable. The markings show the direction in which the power flows. Bottom: 80-pin for hard disk. Top: 34-pin for floppy.

Drive Power Connectors



Four-pole for 5 and 12 volts. Disk drive power connector on the right next to the ribbon cable.

Power supplies are fitted with at least five plugs for delivering power to the drives. If you

need more than this, consider buying one or more splitter cables. A splitter cable providestwo connectors from a single one. The corners of the plugs and sockets are keyed to

ensure correct polarity.

Floppy drives have smaller plugs, which are easily recognized among the cables coming

from the power supply. Finally, there is the large ATX plug that plugs into the power

socket on the motherboard. ATX12 or P6 should be connected where required. The latterprovides extra power for power-hungry processors, as you already learned in Part 1 .

Front Panel Connections

Front panel connections: HDD LED (hard disk light), power (on/ off) switch and RESET switch in the top row. Below: mini speaker.

All motherboards group the pins that provide front panel functions at the bottom right of

the board. You should find these described in the handbook that came with your

motherboard. The abbreviations printed on the board itself are not particularly helpful forbeginners, who may find the following short explanation of the abbreviations useful.

SP, SPK, or SPEAK: the loudspeaker output. It has four pins.

RS, RE, RST or RESET: connect the two-pin Reset cable here.

PWR, PW, PW SW, PS or Power SW: power switch, the PC's on/ off switch. Theplug is two-pin.

PW LED, PWR LED or Power LED: the light-emitting diode on the front panelof the case illuminates when the computer is switched on. It is a two-pin cable.

HD, HDD LED: these two pins connect to the cable for the hard disk activityLED.

Don't worry about polarity. The Reset and On/ Off switch will work no matter how theyare connected, but the LEDs will not light up if they are connected in reverse polarity. If

you can hear disk activity but the LED does not light, simply reverse the plug.



Final Check

Congratulations - you've done it! You have fitted and connected all components. Before

you boot your new computer for the first time, recheck everything. It is very easy to

overlook something obvious.

Consider the following:

Motherboard jumper configuration: are the settings for the processor correct?

Drive jumper settings: master/ slave correct?

Are the processor, RAM modules and plug-in cards firmly seated in their sockets?

Did you plug all the cables in? Do they all fit snugly?

Have you tightened all the screws on the plug-in cards or fitted the clips?

Are the drives secure?

Have you connected the power cables to all drives?

Once you have checked all of the above, you can start your PC and install your operatingsystem.

Documents

Computer Hardware Basic