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Newbie Guides 
Beginners Corner
Buying A New PC
Buying A New Computer
You can't put it off any longer, it's time to buy a computer
and see what all the excitement's
about. It just takes a little understanding of what makes up a computer
system to be knowledgeable and confident enough to buy one without overpaying.
You should have a good working knowledge of the individual components
of a computer and supporting peripherals such as a printer and monitor,
and how each one relates to the overall cost of a good system.
The most common uses for home computers, are word processing, playing
games, and surfing the Internet. With very little effort you can use a
computer to communicate live with family, friends, and business associates
around the world. You can create elaborate designs, modify photographs,
or build Web pages. With very little effort you can even set up your computer
to record the origin of incoming phone calls, as well as send and receive
faxes. Whatever you end up using you computer for, will determine its
capabilities. The first consideration is the computer's brain.
The Microprocessor
When you hear someone speak of the processor or the speed of the computer,
it's the microprocessor they're talking about. Intel is one
of the leading manufacturer of microprocessors and have been supplying
many PCs with chips for years. A couple of other companies that make them
are Advanced Micro Devices (AMD) and Motorola. Each new version of processor
came equipped with more power and features. The microprocessor determines
how fast a computer can accomplish the hundreds of millions of little
calculations it takes to produce useful results for us and is called the
clock speed, and refers to the number of instructions per second the processor
can execute and is measured in megahertz (MHz). Processor speeds have
broken new ground recently and are beginning to be measured in GHz or
gigahertz. If you are buying a computer for simple tasks, and want to
keep the price down, a processor speed of between 600 and 1000 MHz should
be sufficient.
Memory
Memory, more specifically, main memory or system memory used in computers
is called RAM (Random Access Memory). There are several types of RAM,
three of which are common. The first is DRAM (Dynamic RAM) which needs
to be refreshed thousands of times per second. Next is SRAM (Static RAM)
which does not need to be refreshed, making it faster but more expensive
and is usually used in memory caches and not as the computer's main
memory. The third and most common memory is SDRAM (Synchronous DRAM).
This type of memory works by synchronising itself with the microprocessor,
achieving very fast speeds. An off-the-shelf computer should come equipped
with 128 MB to 256 MB of SDRAM. What the computer will be used for will
determine this. If the computer is going to be used to create elegant
graphics or play all-singing all-dancing video games, the more memory
the better. Most computers are equipped with more slots for adding more
memory later.
Hard Drive
A hard disk is the computer's main storage medium. A hard disk is
a magnetic platter on which data is stored. Data or information, means
all of the software, including the operating system, word processing programs,
games, and Web browser. In addition to the software, the hard drive also
stores almost all of the work you produce. When you save your work, it
is stored to the hard disk unless you designate another destination. These
days, hard disk storage capacity is measured in Gigabytes (GB). The data
kept in a computer, whether in the form of commercial software, or something
we create with it, is measured in bytes. To make things easier, computer
people have divided up the designations of the way we store data. We have
kilobytes (KB), approximately 1024 bytes, megabytes (MB), about 1,024,000
bytes, and gigabytes, (GB) equal to about 1024 megabytes. These prefixes
continue into the trillions and beyond, but we'll stick with these
three for our discussion. What will you be using the computer for will
determine the size of hard disk in your computer Today's PCs are equipped
with hard disks of 20 GBs and more although 10 to 20 GB should be more
than enough for the average user, unless they plan to install tons of
software and produce and store thousands of graphics, video, and music
files.
CD-ROM, DVD, and Floppy Drives
Like the hard drive, the CD-ROM, DVD, and floppy drive are data storage
disks. When shopping for a computer there are a couple of differences,
they are portable and hold less information. The CD-ROM which stands for
compact disk-read only memory can hold from 650 MB to 1 GB of data. There
are CDs available that can be read, written to, and rewritten to. The
most important consideration with the simple CD-ROM player is its speed.
Off-the-shelf computers include drives rated as 50X that measures how
fast (in Milliseconds) the computer can access data on the disk, and how
fast it can be transferred. Speeds in the 50X range have the ability to
transfer data at around 7 MB per second. Compact Disk devices can be purchased
that use different interfaces onboard the computer.
DVD stands for digital video disk or digital versatile disk. DVD's can
hold up to 8 GB of data, more than enough for a full-length movie. Though
they were considered optional equipment until a short time ago, they are
starting to come as a standard feature on many computers. With a DVD drive,
you can play movies on your computer and they can also play CD-ROM's.
The DVD drive will be the method to access, record and store all types
of data in the near future and will probably replace the CD-ROM.
The floppy disk is actually a rigid storage disk that measures 3 1/2 inches
and the term floppy is from the days when some floppies were flexible.
We really only have a few options with the floppy drive as they simply
come as standard equipment on all modern computers.
Display Monitor
Computer monitors vary greatly and come in different display sizes ranging
from 14 to 50 inches and more. There are several considerations when buying
a monitor. The first is resolution which refers to the clarity of images
displayed and that depends on pixels. Pixels are individual points of
colour that make up the image on the screen. The more tightly packed the
pixels, the better the resolution. This is referred to as dots per inch
or dpi. Today's off-the-shelf monitors are capable of displaying 1600
x 1200 pixels, a total of 1,920,000 pixels on the screen at any given
time. Another consideration is the refresh rate of the monitor, meaning
how many times per second the screen is refreshed or renewed and is measured
in hertz (Hz). Look for at least 75 Hz for a flicker free screen and high
game frame rates. The dot pitch, another consideration when buying a monitor
is the amount of white space between each pixel. We're looking for
a small number here.
Many computers are sold in packages that include a monitor, commonly 17-inch
and above Virtually everything you do with a computer is shown to you
on a monitor. Photographs on the Internet, word processing documents,
spreadsheets, and almost everything else displayed on a 17-inch screen
is not usually compromised the way it would be on a 15-inch or smaller
display screen. Yes, you can see the entire image by using a scroll bar,
but you don't get to see the whole image all at one time. Again,
what will you be doing with the computer, may require a 19-inch or bigger
monitor. If you are going into business as a graphic artist or Web designer,
you'll probably want higher resolution than you'd find in an
off-the-shelf monitor.
There are flat panel monitors with display screens as thin as one inch
and save a lot of space, but they are still very pricey. Some of the larger
display flat panel monitors are selling for up to £2000. There's
always a premium to pay for new technology and the tubes used to light
the display are mind boggling expensive. For most users, a medium to higher
resolution 17 or 19-inch monitor should be just fine. The monitor is very
important, so I'd go with the best you can afford.
Printer
Of all the peripheral hardware attached to the computer, the printer has
probably come down more in price than any other. At the same time, the
resolution and document quality they produce has improved. You can buy
a decent colour inkjet printer these days for under a hundred quid. I
remember paying £350 for a comparable colour printer only a few
years ago. You will need to maintain a constant supply of ink cartridges
ready to keep the machine running. The average black ink cartridge should
produce about 1000 printed text documents. Like a monitor, a printer is
rated according to the resolution of the documents it produces. Additionally,
the speed of a printer is important. Two types of printer are commonly
found attached to the PC, inkjet printers and laser printers.
Laser printers use a laser beam that projects images onto a drum. During
this process, the laser light alters the electrical charge of the drum.
At the same time, the drum is rolling through a reservoir of toner, which
temporarily adheres to the charged portion of the drum. Finally the drum
to rolls over paper and using heat, the toner is transferred to the paper,
producing the image. Laser printers are rated using several standards.
Many contain their own microprocessor that tells the printer how best
to organise its work. Microprocessors in laser printers range from around
70 MHz to 200 MHz. As with computers, the faster the processor, the faster
the printer runs, but at a higher cost. Printers also have their own memory
so that when you click the print button, the entire job, whether it's
a single page or a hundred, is stored in the printer's memory. The
pages are then printed in the order they were created. When a printer
is able to store printing jobs, it frees up the memory resources of the
computer. When talking about laser printers there is really no "off-the-shelf"
standard. Laser printers can be very task specific, so their components
will vary greatly. The RAM included in such a printer could be as much
as 200 MB, more than most computers. Lower end models might have as little
as 2 MB of RAM. Another consideration when evaluating a printer is the
clarity of the documents it produces. Again, we're talking about
the resolution. Much like a display monitor, this is determined by the
number of dots per inch (dpi) it prints. Lower end laser printers are
often rated at around 600 dpi. More expensive units can go as high as
1200 dpi and more. The PPM or pages per minute a printer can put out will
depend on the content of the document. All printers will produce text
documents faster than graphics documents or photographs. And they will
produce black ink documents faster than colour When looking at the features
of a printer, the manufacturer will quote the PPM for black ink text documents.
Lower end laser printers average around 8 PPM while higher priced machines
can go as high as 18 PPM or more.
With an inkjet printer, images are produced by squirting fine streams
of ink onto paper at high speeds. There isn't much more to it than
that. Since the technology involved here is almost primitive in comparison
to the laser printer. We are looking at virtually the same components
with inkjet printers as with laser printers. That is, inkjets come with
memory, varying resolutions, varying speeds, and network capabilities.
And as with the laser printer, printing speed and resolution can often
be improved with more memory. Because inkjet printers are simpler than
laser printers, they require fewer resources. The memory found in an off-the-shelf
inkjet machine will often range from 2 MB to 8 MB. In high-end printers
the memory can go as high as 70 MB or more. The average dpi for an inkjet
is around 600 and PPM varies from 6 to around 12.
Modem
The modem is a device that allows the transfer of digital information
between two computers over a network and for example allows you to connect
to the Internet. The standard modem used in the majority of computers
today is the 56K V.90. 56K refers to the speed of the data transfer measured
in bits per second, so 56 Kb is equal to 56 thousand (actually K is a
1024) BPS. V.90 refers to a standard that makes use of digital connections.
In many instances modems connect computers over analog telephone lines,
but more and more digital lines are becoming available all the time. The
V.90 standard allows for faster connections speeds when a digital line
is available.
There are more major components on a computer system. You might want
to add a scanner, a digital camera, an enhanced sound, TV, or video card.
A TV card will allow you to watch television on your computer. Some will
let you devote a small portion of your computer screen to television while
you work on other things. The bells and whistles available for computers
are staggering and is the topic for an entire website.
Software
The software is nothing more than an exhaustive list of instructions for
your computer to carry out. Software is what allows us to use computers
for useful work. Until now, everything discussed has been about hardware
and would apply to both PCs and the Macintosh. When it comes to software,
we need to become a bit more specific. Since approximately 90 percent
of home computers are PCs, and this website is about PCs I'll refer to
software on PCs. The good new is, much of the software formerly available
only to PC users, now has Mac versions available.
The most common operating system for the personal computer is Windows.
Regardless of how you feel about Microsoft or Bill Gates, the fact remains,
if you're buying a new PC off the shelf, it's going to come
with some version of Windows, probably Windows 98. Windows 2000 is designed
more towards professional and business use. Windows 98 is still a reasonably
good, fairly robust, operating system with a wide range of functions.
If you are buying a computer to explore the Internet, you'll probably
need a web browser. A web browser is a program that allows you to look
at online documents and web pages. Netscape Navigator is a popular browser
that works much the same as Internet Explorer (Microsoft' browser). Many
people often stay loyal to the first browser they used. The nice thing
with Windows 98 is that Internet Explorer comes with it, so a user is
ready to explore. Another program included with Windows 98, is an email
program called Outlook Express and can take care of most of your email
needs unless you're using an online service provider like CompuServe
or AOL. They have their own way for you to access email that's just
as effective. In addition to letting you run a wide variety of Windows
compatible software, Windows 98 includes many free programs that you can
use. There are a few games such as the card game Solitaire, Minesweeper,
where you eliminate tiles on a grid one by one, trying to avoid hidden
mines, and FreeCell, a card game similar to Solitaire, with 32,000 variations.
There is a paint program that lets you draw and modify your pictures in
colour Windows 98 includes a simple word processing program called Word
Pad, a program you can use to automatically dial your phone, an imaging
program that lets you communicate with a scanner, a calculator, and several
diagnostic utilities for keeping you computer in good shape.
There are word processing programs such as Corel's WordPerfect and
Microsoft's Office. There is software to help arrange your finances,
thousands of games available from casino games like blackjack and poker,
to Duke Nukem, a mad dude who has to shoot everything. There are several
encyclopaedia software packages you can buy, allowing you access to instant
research information. There is software to help you track stocks, mutual
funds and commodities. In fact, if you can think of something you'd
like to do, there's probably software out there to help you do it.
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