BOOT CAMP 021
MEMORY UPGRADE Part 1
Before we begin a few words of warning. If electronic
gadgets keel over and die if you so much as look at them, or you always seem to
have bits left over when you take something apart, please leave now. On the
other hand, if you can wire up a three-pin plug or change a fuse without
electrocuting yourself, adding extra memory to your PC should be a breeze…
This week we'll be looking at what's involved in a PC memory
upgrade and preparing the ground. Next week we'll be doing the deed.
A memory upgrade is the easiest, quickest and most
cost-effective improvement you can make to your PC. The memory in question is
known as RAM or Random Access Memory. It's a collection of microchips that the
computer uses to temporarily store programs and data which it need to access
quickly and frequently. RAM capacity is measured in megabytes, a Windows 95 PC
will operate with just 8 megabytes but 16Mb is considered the safe minimum. 32
megabytes is optimum for most types of home and business software, 64 Mb is
recommended as the starting point for PCs running graphic intensive
applications or fast action games.
RAM chips are mounted on small strip like modules that plug
into sockets on the large printed circuit board or 'motherboard' inside your
PC's system box. The modules are designed to be easy to fit, and impossible (hopefully…)
to insert the wrong way around. If you're properly prepared the whole job shouldn't
take more than fifteen to twenty minutes.
Increasing RAM capacity can make a dramatic difference to
the speed of your applications, you will experience fewer crashes and it may
even extend the useful life of your machine. It is usual to increase PC memory
by a factor of 2, 4, 8, 16 etc., up to the capacity of the motherboard. This
also happens to be a very good time to do it. Memory prices are at a five-year
low; they currently average out at around £1.50 per megabyte.
There are so many different makes and type of PC on the
market that we're going to have to keep this fairly general, and we'll confine
ourselves to Pentium and Pentium-class PCs using Windows 95. Increasing memory
capacity on older PCs with 386 and 486 processors (using Windows 3.1), beyond
16-megabytes, say, gives only marginal performance gains. If you have one of
these machines and want to be able to use the latest software you would be
better off putting your money towards buying a more up to date PC. We should
also point out that more memory won't magically enable a 75MHz or 133MHz
Pentium PC to run software designed for a 200MHz MMX processor.
Begin by familiarising yourself with your PC's current
memory status. It is essential that you have this information, you cannot
proceed without it. You need to know how much RAM your PC has now and what sort
it is. If you can't remember how many megabytes you have open Control Panel,
click on the System icon then select the General tab and it will tell you.
There are lots of different types of RAM but most recent PCs use either EDO RAM
or SDRAM (see Jargon Filter). As a general rule of thumb the chips on SDRAM
modules are thinner and have more pins. It's important to get the same type
when upgrading. If you're not sure check the labelling on the system box, you
may find it mentioned on the instructions or even on the sales invoice,
otherwise you'll have to contact the manufacturer or dealer.
You need to find out how many free memory slots there are on
the motherboard. To do this you have to remove the system box lid or cover and
have a look inside. Have a desk lamp or torch handy, so you can see what you
Before opening a PC we always suggest disconnecting it from
the mains. Some experts advocate leaving the mains plug connected but with the socket
switched off. The idea is the metal case of the PC will still be connected to
earth, so any static charge you may have built up on your body and clothing will
be safely dissipated, as soon as you touch the case. The contrary view is that static
charges are still dissipated by the system metalwork, whether or not the case
is actually earthed. Damage will only occur if a charge is discharged through
vulnerable components. In either case the risks can be minimised with a few
simple precautions. We will look at them in more detail in part two, this week
we're only looking, so you can unplug the mains socket if you feel safer.
There should be a diagram or photograph of the motherboard in
the motherboard manual that should have come with your PC. This will show you
where the memory sockets are located. If they are obscured by ribbon cables gently
move them out of the way. Make a note of how many memory boards are installed, which
sockets are occupied and the orientation of the memory boards. If your PC has 8Mb
of RAM and two memory boards, that's 4Mb per board, and so on. Notice how the
boards are kept in place, most memory sockets have little spring clips at each
end. If it looks as though you are going to have to disturb some cables to get
at the sockets make a sketch of where they go, or take some photographs of the
innards. Replace the case or lid and check everything is working.
Your motherboard manual has other vital data, including the electrical
characteristics of the memory modules. The two items we're interested in are
the number of pins, and the operating voltage. The latter will be either 5 volts
or 3.3 volts, if it's a newish PC. There are three pin configurations; older
PCs (386 and 486s) mostly use 30-pin modules or SIMMs (see Jargon Filter), some
486 and Pentium PCs use 72-pin SIMMs. Most recent Pentium I and all Pentium II PCs
use 168-pin memory modules, called DIMMs.
The motherboard manual should also mention memory capacity and
the combinations of modules you can use. It varies from make to make but newer machines
are usually more flexible. On some older motherboards it may be necessary to
upgrade RAM modules in pairs. Be prepared to compromise, you may have discard
some original modules in order to get the capacity you require. You may be able
to offset the cost of the upgrade by part-exchanging your old RAM modules.
You should now be able to work out the number, type and size
of memory modules for the upgrade. Have this information to hand, plus the motherboard
manual, when you order your memory modules. You may well be asked some additional
questions. If you can't supply all the answers or there are any doubts don't
guess or take chances, pay to have the upgrade carried out by a qualified
Next week, lids off and screwdrivers out.
Extended data out, random access memory, high-speed RAM
chips used on recent PCs with specialised memory controllers
Dual in-line memory module, usually with 168 connecting pins
Synchronous dynamic random access memory, another family of memory
chips that allows data to be accessed at higher speeds
Single in-line memory module, with 30 or 72 connecting pins
The Windows 95 Clipboard is a useful way
of moving files or blocks of text around and between applications but it can
only hold one item at a time, and that is lost the next time it is used. There
is a handy utility on the Windows 95 CD-ROM, called Clipbook Viewer, which will
allow you to inspect the contents of the Clipboard at any time, and save whatever
is in there, for future use. To install Clipbook insert the Windows CD-ROM,
open Control Panel, then click on the Install/Remove icon. Select the Windows
Setup tab, click on Have Disc then the Browse button. Assuming drive 'd' is
your CD ROM, select it and look for a folder called 'Other', in there you will
find the 'clipbook.inf' file, select it and follow the dialogue boxes to 'Install'.
Clipbook can then be found in the Accessories folder on the Program menu.