FOR THE PERFECT
windows display a tantalizing range of PCs. But do not give in
to the sales pitch and choose one that looks or sounds good.
Instead, remember these few valuable tips so that you buy the
most appropriate PC and peripherals that will best suit you
that youíre serious about buying a computer you may consider
the options available. If youíve ever visited a computer
store, it is very likely the salesman tried to push you a
computer by mouthing a whole lot of technical jargon. However,
knowing what goes into the making of a complete personal
computer (PC) will help you make an informed decision in
buying the right one. Thus, in this section Dr.KSM will
lead you step by step to what makes a computer tick, and what
you should be aware of when you actually go out there move and
buy your own PC.
PCs are of two types-the great looking iMac form Apple and the
wide range of standard IBC compatible PCs. How does one decide
which one to go for? The
iMac is pretty good for games, multimedia and Internet
connectivity and its user-friendly interface. However, the
software titles available for an iMac are pretty limited.
Also, Upgrading an iMac isnít generally possible.
the other hand, IBM PCs allow extensive upgrading and have a
lot of software and hardware options. Whatever your choice,
PCs are ideal for office as well as home usage. Even if we put
all IBC compatible computers under one roof, each machine can
be very different from the other in terms of the component
they house inside.
your budget in mind, make a careful choice over which PC would
best suit your needs.
Processing Unit (CPU)
CPU is the core unit of the computer. Akin to the brain, this
is one critical component that decides how fast your computer
will be. An indicator of speed is generally the clock speed of
the CPU, given in Mega Hertz (MHz). Generally, higher the
clock speed, faster the CPU. The CPU also houses a small amount
of memory called cache (pronounced: cash) the helps
speed up memory accesses. Thus the amount of cache a CPU
possesses serves as an indicted indicator of its speed. There
are quite a few choices in CPUs, each having a balance between
performance and cost.
one end of the CPU spectrum are the Pentium ĖII, Pentium Ė
III and Pentium - IV class CPUs, with fast execution
and high clock speeds. The Pentium ĖIII isnít much different
from its predecessor (the Pentium- II), but it promises
significant speedups, especially in 3D games, mathematical software
and spreadsheets. The Pentium-IV has added a few new
instructions that help software do match faster. The catch is
the application runs faster only if the new features are
explicitly used. Designed specially for repetitive
complex calculations, these instructions will definitely
help upcoming 3D games to
become more realistic. What it means it that all the
existing applications will run at about the same speed, but
those taking advantages of the new features in Pentium-IV get
a significant boost. And as more and more software being
supporting these features, the Pentium ĖIV
is becoming a successor to the Pentium-III.
the other end is Celeron series. Introduced after the
Pentium-II the Celeron CPUs, have slower performance, at a budget
price. The slower speed comes partly due to reduction in the
CPUs cache memory. Earlier Celeron chips had no on-chip cache.
However in its recent incarnation, the Celeron is a stripped
down Pentium-II with an affordable price tag.
new contender on this side is the Advanced Micro Devices
(AMD). Although not as well-known, AMDís K6 and recently
introduced K7 processors churn out good performance at rock
bottom prices. Though the AMD has not made a mark in India,
the K7 processor beats Pentium-IIIís
performance, but at equal prices.
motherboard is basically a printed circuit board housing all
the slots for connecting the CPU, sound card, video card, hard
disk, memory and everything else that goes in a computer. It
also hosts basic hardware such as a floppy disk and hard disk
controller, communication ports and sometimes the newer USB
(Universal Serial Bus ) interface, Like glue, the motherboard
connects the computer parts together and makes it all work as
the motherboard hosts a connector for the CPU, only the CPUs
compatible with that specific connector will work on the given motherboard and vice versa. For
example, the Pentium and AMD K6 can be connected to a Socket 7
motherboard. But the Pentium -II can only be used with a Slot
I Motherboard that is designed to accommodate CPUs featuring
Slot I type connectors which are motherboard supports defines
which cards can be connected on your computer and overall how
fast it will work.
PCI based motherboard with support for ISA and AGP slots is
preferred, as it will give high performance in addition to
compatibility with older ISA based cards. The chipset on which
the motherboard is based is what decides its features and
capabilities. Avoid older 440 LX motherboards for the
Pentium-II/Celeron range, as they are pretty slow and have
been replaced by faster ones such as the 440 BX Motherboards.
For PIIIs, the 820 chipset is generally adequate. Support for
the USB interface should also give future compatibility to
upgrade to newer peripherals (such as scanners, mouse,
keyboard, etc) designed for this connector type.
the components inside the computer (video card, sound card,
CPU, RAM, etc) are connected to each other by a complex
interconnected network of wires known as the bus. The main types
of buses are ISA and PCI. The industry standard Architecture
(ISA) bus standard is the older and slower of the two. Brought
out in the early 1980s, support for ISA is being eroded by the
PCI standard. PCI, or Peripheral component interconnect,
supports plug and play and is faster than ISA. AGP
(Accelerated Graphics Port0 is another bus system. But
unlike PCI or ISA, AGP was exclusively designed for
faster connections between the video card and the computer
memory. Most new computers have an AGP slot inside where a
video card supporting the AGP standard can be connected. In
most cases, an AGP card
outperforms its PCI equivalent due to faster memory access.
a human brain, the computer houses its memory separate from
the CPU. Computer memory, known as Random Access Memory or RAM,
is measured in the number of byes it can store. A byte is a basic
block of memory, composed
of eight bits, each bit having either a one or zero as
its value. Most computer memory
nowadays is measured in Mega Bytes (MB), which are
approximately 1,000,000 (million ) bytes.
amount of memory needed is generally based on your usage; the
more power hungry applications you use, the more memory you
will, need. Although having more memory than needed wonít
hurt, having less certainly will make its impact felt on
performance. Hence the amount of memory in a system also ends
up determining its speed. In fact, after the CPU, memory is
the next component that affects a computerís speed.
is generally available on small printed circuit boards housing
a bunch of small chips on its surface in the form of modules.
You however, wonít even be coming in visual contact with
these as they lie inside your computer. Today, around 32MB is
considered as the shoestring value that should just about make
the computer start with windows 95. If you plan on using
windows 98 and other software like excel or word, which you
most certainly will, then 64MB is the baseline that you would
probably need to comfortably. And if 3D games and complex data
hogging applications is what you want, 128 MB of memory should
be your target.
computer operates on data in binary form. The binary number
system has only two numbers (0 and 1) as opposed to 10 numbers
(0 to 9) in the decimal system that we use. Computers use
binary mainly for its inherent simplicity. Also, since Boolean
logic also has two values: true or false, the binary system
lends itself easily to logical operations that the computer
performs. In computerdom, single digit in binary is called a
bit. A collection of four bits is called a nibble, although
the term is rarely being used today. Eight bits make a byte.
Bytes are like basic chunks of binary data that the computer
uses to perform all its operations.
RAM is the computerís short-term memory, the hard disk its
long-term counterpart. A hard disk does what the RAM canít ;
it stores information even after the computer is switched off,
while RAM loses it the moment power goes down. Although both
memory and hard disk store data, hard disk is simply a huge
storage device that the computer uses to store all the files
to the computer, without them we would be stuck with floppies
and clunky DOS like interfaces. Hard disks are available in
two varieties: IDE and SCSI. IDE hard disks are the most
popular, since they donít require any extra components and
are relatively cheaper. These are ones that normally come with
a computer. SCSI hard disks on the other hand, require a SCSI
controller and are generally more expensive. But what they
take, they make upon in their faster speeds. Also, a SCSI
controller and are generally used except in critical process
and where speed is of prime importance.
disks now come with capacities measured in Gigabytes (GB); one
GB being equivalent to more than 1,000,000,000 bytes! A 4.3 GB
hard disk is the current baseline for housing all the software
you need on your PC and having space left for your documents.
Generally a maximum of four IDE hard disks can be connected on
a computer, providing for an easy way to upgrade. Still more
can be connected, but that requires you to opt for the SCSI
monitor though among the most expensive, is generally also among
the ignored components of your computer, You may insist on a
cool new CPU have oodles of RAM installed and then probably
won't care too much about the monitor. But consider this all
the time you sit in front of the computer, your are staring at
the computerís monitor. And a monitor is expensive, and it
doesnít allow upgrading. So, carefully choose and buy the
best monitor you can afford. Having a good monitor definitely
goes a long way in deciding how your computing experience will
be. Get a blurry, small monitor and all you've got is
headaches and aspirin. And not to forget eyestrain!
monitorís size is described in much the same way as your TV
in inches. Most computers today come with a 15 inch monitor.
Avoid 14 inch monitors they look like small cabin windows.
Check up on the difference between a computer having a 15 inch
monitor and its 17 inch counterpart. Recently prices of 17
inch monitors have gradually become lower, making an upgrade
to the 17 inch ones more economical. So if you can afford a 17
inch one, go for it.
few things you should know besides the size of a monitor are
its dot pitch and maximum resolution. The dot pitch determines
how crisp and clear your monitor can show. Lower the dot
pitch, better is the clarity of the monitor. A dot pitch of .28
is standard. But there are monitors offering a .26 dot pitch.
you can actually get to test the computer, check if the screen
appears crisp and there are no noticeable deformations in color
of shape. Also check if you can spot any obvious flickering of
the monitor. If the monitor appears to be flickering too much,
using it for an extended period of time will make your eyes
the stuff you see on the Monitor, the windows buttons, fancy
icons and cute pointers are there courtesy of a video card
residing inside the computer. And even though a video card is
important in a computer's drawing speed, a few dealers tend to
cut corners when it comes to choosing the right one for a
given computer. Every video card has its own special memory
that it uses for rending the display, known as Video RAM(VRAM).
The amount of VRAM present in a video card determines how
detailed your display can be. How much VRAM you need is
determined not only by what you run on the computer, but also
by which monitor you have. In general, a 4 MB video card is fine for basic use with a 15
inch monitor. For a 17 inch one, around 8 MB should suffice.
thing to watch out for is which bus the video card connects
to. There are there are three types of slots inside your
computer where the video card can be plugged in ISA, PCI and
AGP. ISA video cards are pretty old, and just avoid them,
unless you want an authentic 80ís experience with windows
95. It is more likely that your video card will be PCI or AGP,
AGP being the faster one among the two. The one you choose
depends on whether your computer supports AGP or not. If your
computer supports AGP, go for an AGP card.
exact card you need basically boils down to what you will be
doing with your computer. If you plan to play new 3D games on
the computer, then a 3D accelerated AGP card from a popular
company is recommended. These cards although a tad bit
expensive, are worth the price for their impressive 3D
rendering speed that new games demand. However, if basic
office work is what you have in mind, then a simple PCI / AGP
card with around 2 to 4 MB of VRAM
Disc-Read Only Memory (CD-ROM)
and Digital Versatile Disk (DVD) drive
CD-ROM with its high capacity (650 MB) can be likened to a
removable hard disk. However the resemblance ends there, for
CD-ROMs cannot be rewritten. Once
a CD-ROM is created, its contents cannot be deleted or
changed. However, this hasn't stopped CD-ROMs from
proliferating in the computer market. Due to its huge storage
capacity, everything from games to business software to office
suites, literally everything under the computing sun is
distributed on CD-ROMs. And although not vital for the
computer to work, the CD-ROM is indispensable nowadays due to
its widespread popularity. To read data from any CD-ROM you
need a CD Ė ROM drive, which fits into your computer in much
the same way as a floppy drive does. Ordinary CD-ROM drives
are limited to playing audio CDs and reading data off CD ROMs.
But there are other available, which allow you to create one yourself.
Known as CD-R drives, meaning CD Recordable, you can use these
to create CD- ROMs yourself. However as a doctor, you will rarely
need to create one.
CD-ROM driveís sped is given in a speed factor followed by
an 'x' like a 16x CD-ROM drive, for example. Choosing a good
CD-ROM drive amounts to getting the one with the fastest speed factor. In simple words, go for the highest speed number and
you have got yourself nice drive.
big brother of CD-ROM is the DVD which boasts of a huge
capacity and superior performance. A single DVD can hold data
of about two CD-ROMs and is faster. However, the evolution of
DVD hasnít taken off well and although of late a lot of
movies are available in DVD format, we have yet to see major
software being etched onto DVD disks. However, most DVD drives
can also read standard CDs and CD-ROMs. So if you have an
inclination to watch high quality movies on your computer and
donít mind the slightly higher cost, then a DVD drive is for
sound card is what makes your computer do a lot more than just
beep at you it lets it play music and sound. If you plan to
use programs that use audio capabilities of your computers
such as multimedia titles, moves or speech recognition, then a
sound card is a must. When buying a sound card, you should be
aware of the maximum sampling rate (measured in Kilohertz)
that a sound card supports. Most sound cards can sample at a
rate of 44KHz, which is fine for almost all audio processing. Avoid
buying older cards with lower sampling rates, as they may not
come with drivers needed for their proper functioning.
size of audio data that the sound card can process in a given
instant is also important to the output sound quality. The
higher the number of bits it can sample at a time, higher is
the quality. A 16 bit sound card should be adequate, but if
you are thinking of using your computer as home theatre system
or the likes, go for a 32 bit/64 bit sound card. Also try
getting one that is SoundBlaster compatible, as these are the
ones most supported on the PC platform.
with the above given parts, a PC generally is also equipped
with stuff which hasnít changed much since the 1980s. Take
the Keyboard for example.
It has been shipped with every PC ever assembled and hasnít
changed much since its inception. Tailored after the
typewriter, the QWERTY keyboard (named after the six top left
keys on the keyboard) has always ruled computers. And unless
speech recognition comes of age, the keyboard is bound to
adorn every computer userís desk for another decade or so.
peripheral that is found on almost every PC since Windows
became the popular operating system is the Mouse.
Mice come in lot of types and shapes but the basic design remains
the same: a handheld device with two or more buttons.
Floppy drive is the third
device that comes along as a standard in all PCs. Floppies and
their drives come in two sizes: 3 Ĺ inches and 5 ľ inches.
Both are common, although the 3 Ĺ inch floppies are more
with the standard computer configuration, need for more
peripherals connecting to your PC is more than ever before.
Peripherals allow the computer to input or output information
in more than one way, making a computer more useful. For
example, instead of typing printout your received, wouldnít
it be great if you could somehow get your computer to read the
print itself? Its possible using a scanner coupled with an OCR
(Optical character Recognition) software. In the following
passage, we will show you some peripherals that should help
your make the most of your computer.
using your computer to create invoices, health records,
prescriptions and the like is what you have in mind, you age
going to need a printer. There are quite a few types of
printers for the PC dot matrix, bubble jet, inkjet and laser
printer. Each of them is outlined below to help you decide the
one for you.
matrix printers have an array of small print heads and their
impressions on an ink ribbon are transferred onto a paper, thereby
printing characters on the paper. Among the oldest technologies,
the dot matrix printers now have limited use in that of
printing pure text. Anything other than text and printer will
show poor quality. In short, if you are looking at fast
printing of text only dot matrix is your choice.
inkjet and the bubble jet printers although different, work
similarly by placing ink directly onto the paper. The inkjet
printer squirts ink, while the bubble jet prints by heating
ink to the same effect. In fact, the bubble jet printers can
be likened to an offspring of the inkjet family. Inkjet
printers are very economical at the performance they give and
they are getting better at it.
king among printers is the laser printer which represents the
ultimate in printing technology. Dishing out fantastic print
quality (photo realistic), the cost of their color versions
however are sky-high. But being a doctor who doesnít want to
dabble in 3D modeling and graphics, it makes sense to buy an
inkjet/bubble jet printer. However, if all you need is text,
then go for dot matrix ones. When choosing an inkjet, bubble
jet or laser printer cheek on its maximum printing resolution.
The printing resolution determines how much detail can be
crammed into an inch. Measured in Dots Per Inch (dpi), ones
with resolution of around 720 dpi should be adequate for
quality letters and documents.
like the way we talk over the phone, computers can be
connected to each other through modems, thereby allowing files
and data to be shared. So you could get that program your
friend has without using a floppy disk. If both of you have
modems, then all you have to do is connect and use the right
software to transfer the file to your PC. Having a modem also
allows you to connect to the Internet and that is perhaps the
sole reason why modems are popular accessories.
An increasing number of computers
nowadays come with a modem bundled along with it. Modem speed
is measured in the number of bits per second (bps) that can be
sent over the phone line, Though a 33.6 Kbps (33,6000bps)
modem is decent enough to connect to the Net, todayís
standard is 56Kbps. However, note that
a modem can achieve maximum given speed only when
modems on both sides support it and the phone line is
reasonably clear. Some modems have extended features which may
suit your needs such as built-in voice mail, support for
sending and receiving faxes, built-in answering machine
beckons you, go forward with a modem.
the printer takes a hard copy from the soft one, the scanner
works in reverse. Grabbing a soft copy from a given hard one.
Although used mainly by graphics professionals for getting
photos in computers, scanners are nowadays being widely
employed in a number of other fields. Coupled with a text recognizer
(OCR software), It can function to read printed matter. It can
also be used for keeping records of documents, by scanning
them into a computer and keeping the soft copy instead.
in what way could it help a doctor? One possible use could be
scanning the patientís photo or x-ray plates into the
computer and incorporating them into a database of all your
patients. Currently in experimental phase, a project similar
to this is being developed by MIT, where, a special dedicated
X- ray plate scanner has been developed. Coupled with
specially developed software it allows doctors to scan a
single x-ray plate and then use the software to simulate how
x-rays of the same place taken with different intensity
and exposure times would look like, thereby decreasing the
need for taking multiple x-rays. Another use is to unclutter
your desktop by scanning and categorizing all documents so
they can now be retrieved efficiently just by a click of a
have a limit to the maximum details that they can scan in an
image, and this is measured in dots per inch. A maximum
scanning resolution of around 600x 1200 dpi should be fine for
scanning just about anything
photos and x-ray plates.
Power Supply (UPS)
is the worst nightmare that can befall a computer user?
Indisputably, itís working for
hours on end without a break and then having your
masterpiece wiped out by a power outage just before saving it.
It is not surprising when you hear that a number of people
have faced this disaster. However, what can avert such an
eventuality is a device known as the UPS.
a highly glorified battery, the UPS is what brings a computer
back to life when its oxygen supply is cut. Just when the
power outage occurs, UPS kicks in and allows you to save your
work and gracefully shutdown, thereby avoiding all the
shouting and swearing that would normally follow otherwise. If
your PC is set up in a place where power supply is unpredictable
and blackouts often occur, then what is needed is a UPS. A UPS
provides limited power supply which is measured in KVA (Kilo
Volt Ampere) and decides
just how much load it can take, And since all that is needed
is that your work is saved and later shut down when the power
outage occurs, a UPS of around 0.6 KVA that will last around
five minutes should suit your needs.
you intend to travel a lot and would like to carry your PC
with you, a desktop computer may not be a good idea. A laptop
computer would best suit your needs. Laptops may look
deceptively small, however these bonsai PCs give you what
desktops cannot Ė computing freedom. Great for presentations
and working during air travel, laptops allow you to use idle
time to the maximum. Choosing a laptopís configuration
amounts to about the same as that of a desktop, but there are
also some extra things to watch out for. Laptop screens are of
two types Ė active matrix and passive matrix. Passive matrix
screens cost less but have a lower clarity and limited field
of view. In comparison, though active matrix panels cost much
more, it can be viewed nearly edge-on without losing any of
laptops have different pointing devices like track points,
track balls and track pads. A track point is a small stub in
the middle of the keyboard that can be used as a joystick to maneuver
the pointer. A track ball does the same by allowing you to
move a small ball attached to the notebook while a track pad
uses a flat surface that you touch to move the pointer.
laptops come with a modular design allowing your to attach and
remove CD-ROM drives, hard disks or extra batteries. Built Ė
in PCMCIA slots allow laptops to connect to devices like hard
disks, network cards, modems and external CD-ROM drives.
Having a modem either built-in or in a PCMCIA slot should keep
you connected to Internet. However, to make a presentation
right off your laptop would mean that you use an active matrix
screen, as it would be clearer. On the whole, a full-fledged
laptop computer should set your off by around Rs. 70,000 to Rs.
1,00,000 and more. Other budget laptops with basic functionality
can be had for around Rs. 50,000. But for the freedom it
offers, it would well be worth it. Dr.KSM uses Compaq
Presario 1200XL Model Laptop for all his work.
it all together
now you now almost all the parts that go into creating a
complete computer system. But like a jigsaw puzzle, all this
information is of use only when the pieces are brought
together and create a whole picture. So to bring all the parts
together, we will present you with three basic configurations,
which you can customize depending upon your needs to create
the perfect PC configuration for yourself. Keep in mind that
these configurations and their prices are bound to change in
the near future.
: Celeron or AMD K6-II (350 to 500 MHZ)
: 32 to 64 MB
14/15Ē SVGA color
: 6.3 GB
: 4 MB Video RAM
CD-ROM : 48x speed
: Sound card, modem , etc.
price : Rs. 25,000 to Rs. 40,000
: Celeron (466
to 600 MHZ)
: 64 MB
to 10 GB
: 4 to 8 MB Video Ram
CD-ROM : 48x speed
: 32 bit PCI
: Printer, scanner and modem
price : Rs. 35,000 to Rs. 60,000
: Pentium ĖIII (500 to 800 MHz) or Pentium IV (1 to
: 128 MB or more
GB or more
: 3D accelerator, 8-16 MB
CD-ROM : 48x or more / DVD ROM
: 32 bit PCI with wave table
: Inkjet printer
price : Rs. 60,000 to Rs. 80,000
Copyright © 2002 Dr. Subrahmanyam