your computer runs slowly overall,a new processor can potentially
improve the performance.The motherboard and the processor work as a
team and most motherboards work with only a short list of processors.Motherboard is
the big circuit board inside the case that every thing plugs into.The
capabilities of the motherboard you have determine the processor you
can use, the type amount of memory you can have ,the video card type
and more.A computer that uses an old processor is probably an old
computer with other old components.The hard disk is probably small,and
the memory insufficient for today's programmes.It is cheaper to buy a
whole new computer than to upgrade individual parts on it.
There are two kinds of processors you can buy: Replacement processors and Upgrade processors.Replacement
processors are "regular"processors,the same type you would buy if you
were creating a whole new system.Your system is a good candidate for a
replacement processor if your motherboard's manual indicates that it
can accept a faster processor than what you currently have."Upgrade
processors"are designed to work with a variety of motherboards and to
replace a variety of existing processors.These typically double or even
trible the speed(in MHz)of your current system.
of adequate memory is one of the most common reasons a computer runs
slow.When there is not enough memory ,windows relies heavily on virtual
memory which is slow and inefficient.
you want to purchase memory be sure to know what kind of memory your
system needs.The memory sold these days are of two types:-SIMMs(Single
Inline Memory Modules) and DIMMs(Dual Inline Memory Modules).Newer the
system more likely it uses DIMMs.
SIMMs are found in 486 and
some pentium systems.SIMMs come in 72-pin or 30-pin sizes,72-pin being
the most common.It comes in three varieties
1) True parity memory:- This
memory is for systems that require parity memory.Many older 486 systems
require true parity.Look for a 36 in the specifications for parity
memory.,as in 16X36-60ns.
2) Fast page mode(FPM)memory.FPM
is generic memory.It works in just about any system that requires
non-parity memory and doesnot mention anything about EDO.Look for a 32
in the specifications for this,as in 16X32-60ns.
3)Extended out(EDO) memory.:-This
is a newer,better kind of non-parity memory.Many of the pentium class
systems use it.Most of the systems currently being sold use 168-pin
dual inline memory modules(DIMMs).One variety,called S-DRAM DIMM,is the
latest rage because it is faster and better than SIMM.You can find DIMM
in PentiumII and Pentium III systems. YOu can buy memory modules in
various denominations ranging from 256K(1/4 of MB)to 128 MB and
higher.You need to make sure when choosing a denomination that your
motherboard supports it and that you are not mixing denominations in a
memory bank.Each DIMM slot is a bank unto itself,so you have not to
worry with DIMMs;but most SIMM slots work in pairs and you must have
the same denomination in each slot of pair. RAM also comes in different
speeds,measured in nanoseconds(ns).A lower number is faster and faster
is better.Most RAM you buy today is 60 ns,but you can buy 70 or 80 ns
at a discount.
Determining the memory you need:-To determine what kind of memory to buy you need to know two things. 1)What open memory slots you have on your motherboard.
2)What type,speed,and denomination your motherboard accepts.
Hard disks are distinguished from one another in several ways: the
interface they use,their capacity and how quickly they can read and
Chosing an interface:-Your current
hard disk is probably an IDE of some variety.These drives offer decent
performance at a very good price,and they run on almost any
computer.Your computer has built in support for four IDE devices, so
you can probably add another IDE drive without buying anything
extra.The most common types of IDE-compatible drives are EIDE(E stands
for enhanced) and ATA-2,There is also a new IDE type,UltraDMA(UDMA)IDE
which offers improved performance over other types of IDE drives.
can also get SCSI(Small Computer Systems Interface) hard disks.These
hook up to SCSI interface cards, so if you don't already have a SCSI
interface card in your system,you need to buy one if you want to use a
SCSI hard disk.SCSI hard disks are usually more expensive than IDE
drives and are considered superior.
When chosing a new hard disk
capacity always overestimate.you can buy anything from 1.2 GB to 100
G.B or more.In additiontn to capacity you also need to consider the
physical size of the drive to fit in the space available in your
Hard disks have two critical measurements.
1) Average access time:-It
is the time it takes for the drive head to reach and read the average
bit of data.It is measured in milliseconds(ms).The lower the number the
faster the drive.A decent speed is 10ms.
2)Data transfer rate:-
This measurement refers to how quickly data moves from the hard disk to
memory.The higher the number the fater the rate.Look for adata transfer
rate of 11 to 16 megabytes per second.Popular brands in hard disk
include Maxtor,Western,Digital,Seagate,Quantum,and JTS.
Repartitioning the hard disk:-this
is not necessary to correct system problems.The only reason to
repartitionthe hard disk is to allocate the space on the hard disk in a
repartition,you also need to reformat.If you don't
repartition,reformatting is optional.Formatting adrive wipes every
thing from it:programmes,data,system files,startup files and so on.It
provides a truely clean slate on which to reinstall,guaranteeing that
the files that were causing the problem are eradicated.Reformatting is
suggested in the following cases.
refers to the diameter of the screen which range from 14 inches to 21
inches.When you see the listed size you may see two sizes like
17-inch(15.9-inch viewable);so while comparing the sizes of two
monitors,compare the viewable size of the two,which really matters.
monitor's maximum resolution refers to the maximum number of seperate
dots it can display horizontally and vertically.Many small monitors can
display up to 1024X768---that is 1024 dots across and 768 dots
down.Larger monitors display much higher resolutions;the better quality
the monitor,the higher its maximum resolution
video display is made up of tiny dots.The dot pitch is the
measurementof how close together the dots lie.A dot pitch of .28 is
considered the min.adequate amount.Lower dot pitch is better.Higher dot
pitch makes the picture less crisp.
The most common kind of monitor is called dot trio shadow mask.These monitors deliver clean edges and sharp diagonals which is important for showing text on screen.
Another kind of monitor has an aperture grille
rather than dots.Their performance is measured in stripe pitch rather
than dot pitch.Look for a stripe pitch of .25 or less.These monitors
have superior brightness and contrast,but their poorer diagonals make
them less well suited for diplaying text.
A third kind of monitor is a slot mask>It combines the attributes of a shadow mask and a aperture grille.It uses a .25mm mask with eleptically shaped phosphors.
final kind of monitors,LCD, is mostly found on laptop computers..Some
manufacturers are beginning to use LCD in large desktop monitors with
stunning results.These monitors can be nearly flat and the displays are
Interlacing and Refresh rate.To
understand these factors we need to know abit about how monitors
work.The screen is made up of tiny dots that contain particles that
glow when alight hits them.A light gun(or a set of three guns:blue,red
and green) moves very quickly over the monitor,dot by dot,making each
dot glow with the appropriate color.Without being refreshed by the
ligght gun,the particles in each dot fade quickly,so the light gun must
refresh each particle hundreds of times per second.The rate at whichthe
particles are refreshed with the light gun is the refresh rate.Some times the display appears flickering as a result of low refresh rate.
On some cheaper monitors ,the light gun simply cannot keep up;to compensate,the manufacturers use a scheme caled interlacingto
keep the display readable.With interlacing,the light gun scans
alternate horizontal lines, rather than every line, on each pass, so
the gun can make twice the no. of passes in a given amount of
time.Because the horizontal lines are so close together our eye cannot
pick up that evry alternate line is not refreshed.
monitors are ones capable of non-interlaced operation and a high
refresh rate.Look for a monitor with a maximum refresh rate of atleast
Other Monitor Features.:-Here are some extras which are oprional in a monitor.but are nice.
drives come with speeds of 16x,24x, 24/32x and so on.The "x" here
refers to the speed of CD_ROM drive originally manufactured.The speed
is the speed of CD-ROM drive at which it is capable of reading
information from the disc.Some time the manufacturers mention two
speeds such as 24/32x which means it can read the data near the center
of the disc at 32x.The outer part of the disc is read at a much slower
speed (for example 16x).Though for playing games more speed may be
necessary, it is probably not worth springing for a drive faster than
24x.Most soft ware in the stores today requires only an 8x or 16x
CD Interfaces:-When CD-ROM drives
first came in the market, the most popular models were SCSI(Small
Computer System Interface) drives.You have to insert this special SCSI
interface card into the computer's expansion slots in addition to
buying the CD-ROM drive.There were improvements and the CD-ROM drive
came with SCSI card i.e. you have not to buy and set up SCSI card
However the dominant type of interface today for
CD-ROM drive is IDE.This is the same interface your computer's hard
drives hook into,so it is already there in place -nothing extra to
buy.Most motherboards let you have four IDE drives,so unless you have
four seperate hard disks already,you probably have an open IDE
DVD:-DVD drives are like super CD-ROM
drives .They can read not only regular CDs but also special DVD
disks,which can hold as much as 8.5 gigabytes.That is 133 minutes of
video- an entire full-length movie.Newer DVD drives available today can
also function as regular CD-ROM drives;so you can replace your
computer's old CD-ROM drive with DVD.
What are CD-R and CD-RW:-CD-R
is recordable CD-ROM drive which act just like regular CD-ROM drive
except you can create your own CD-ROMs with them.CD-RW stands for
CD-rewritable.With CD-R you can record to a disk only once.However with
CD-RW you can record multiple times on the same disk.CD-RW drives also
can perform like CD-R drives.If you are going to buy a DVD or
CD-rewritable drive,go with a brand name.
scanner digitises pictures so you can use them in computers.Some
scanners also come with Optical Character
Recognition(OCR)software,which allows you to scan text and translate
the picture of the text into real text in aword processor;but in
practice OCR software makes so many mistakes that it is not worth going
in for such type of scanners.The resolution of a scanner's scanned
image is measured in dots per inch, or dpi, just like printer
output.(min 300 dpi).
Scan quality:-Scanners come in
black and white and color model;however color models dominate the
market.The quality of the scanner is expressed as a number of
bits.(ranging from 30 bit to 33 or 36 bit or more).
scanners come with their own interface cards;others require you to have
a SCSI card.A third category attaches to your parallel port,which means
you don't need an extra interface card.It provides a pass-through for
your printer,so you can connect your scanner and printer at the same
time to share the port. If your system has a USB port,consider a USB interface for your scanner.