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BOOT CAMP 034
MYSTERIES OF THE SILVER DISC
The CD-ROM is one of the unsung heroes of computer
technology. Without it it's unlikely the PC market would have developed
anything like as rapidly. The benefits are obvious. A CD-ROM disc can hold up to
650 megabytes of data and the latest models are almost as fast as hard disc
drives. The drive mechanisms are relatively inexpensive, discs cost next to
nothing to produce, they're easy to distribute and fairly robust.
Needless to say CD-ROM has its downside. It is a major source of confusion, and
errant drives can cause a whole heap of problems. CD-ROM has created a
generation of 'bloatware', huge, overweight programs and applications that
swallow up hard disc space and force users to constantly replace and upgrade
their machines. Freebie CD-ROMs are also responsible for much of the clutter
that accumulates on PC hard disc drives, reducing performance, causing conflicts
and crashes.
For good or ill CD-ROM is now a fact of PC life so it is
worth making sure that the drive mechanism in your computer is correctly set up
and properly maintained. While we're at it, we'll also take a look at some of other
things your CD-ROM drive can do and to round off, a quick peek at son-of
CD-ROM, the DVD or digital versatile/video disc.
We'll begin with a quick health check. From the Start menu on
Windows 95 click on Settings then Control Panel. Double click on the System
icon and select the Device Manager tab. The CD-ROM listing is normally at the
top of the list, hopefully you won't see any small exclamation marks next to it.
If you do that indicates there is a driver conflict, which may be affect the
operation of your drive. To resolve the problem start the Hardware Conflict Trouble-shooter
utility program; click on Help, type 'Conflict' into the index window and
follow the instructions.
If the listing is clear click on the plus sign next to it and
make sure the CD-ROM drive model number that appears is the correct one -- this
information should be included in the instructions or manual that came with
your PC. Next, click on the Performance tab, select File System and the CD-ROM
tab. Assuming your PC has at least 16Mb of RAM the Supplemental Cache slider
should be set to 'large'; check the window below shows the right type of CD-ROM
drive, i.e. 'Quad Speed or Higher', etc. If you make any changes don't forget
to click on apply, and you will be asked to restart your machine.
Generally speaking CD-ROM drives are fairly reliable but
things can and do go wrong. The commonest problems are the PC not being able to
read from the drive, your PC telling you the drive isn't available, or it doesn’t
exist! This is almost always cause by the ribbon cable that connects the drive to
the motherboard (or controller card, on older models) becoming detached. It's
easy to put right, though it does involve removing the lid and taking all the
usual precautions, like switching the PC off first, and touching the case
metalwork, to dissipate any static charges that may have built up on your body
or clothes.
Usually the cable is still in the socket but has worked
itself loose. All that's needed is a gentle push to re-seat it. However, it if
has fallen out it's important to make sure it goes back the right way around. One
edge of the cable ribbon should have a solid or dotted red line this indicates
pin 1. The corresponding pin 1 on the socket should be marked on the socket, or
on an adjacent label. If you do manage to get it in back to front no damage should
occur, but obviously the drive won’t work.
If the drive is completely dead, a detached power supply plug
is possible, but rare. If the tray won't open, or a disc becomes trapped
inside, you can manually open the draw on most drives using a paperclip. There
should be a small hole on the front panel close to the drawer. Open up the paperclip
and push one end into the hole, this will unlock the tray, so it can be pulled
out. While we're on the subject of wayward cables, this is often the reason
behind a CD-ROM drive not being able to play audio CDs. A thin cable connects
between the drive and the soundcard (or audio input socket on the motherboard).
It's not unknown for the cable to be the wrong type, or missing altogether on
new PCs. In such cases CD-ROMs operate and load normally, with sound, which can
seem strange.
If you want your audio CDs to start playing as soon as
they're loaded then go back to Control Panel click on the System icon and select
the Device Manager tab. Click on the plus sign next to the CD-ROM listing, double-click
the drive listing and select the Setting tab. Check the Auto Insert Notification
check box and restart Windows.
Another common problem is the drive not working in DOS,
though it functions normally in Windows and a DOS window. This can happen
suddenly, and for no particular reason or it may be that the drive has never
worked in DOS. In both cases the likely culprit is a corrupted or missing DOS driver.
The DOS driver software should have been supplied with your machine, normally
on a 3.5-inch floppy disc. Open the disc using Windows Explorer, on it you will
find a Readme file that will outline the installation procedure.
As well as audio CDs virtually all drives made within the
past three or four years can play other types of disc, though some may require
additional hardware or software. Photo CDs should be no problem, though you
will need a viewer or graphics package, like PaintShop Pro or PhotoSuite. Most
drives can read homemade CD-ROMs, there are two types: CD-R, where the discs
can only be written once, and CD-RW (read, write), that can be used over and
again. Some earlier drives may have trouble with the latter type.
The next generation of shiny discs has just begun to appear,
DVDs are the same size as audio CDs and CD-ROMs but they hold much more data, almost
thirty times as much with future disc capacity reaching 17 gigabytes! There are
two types of drive, read-only or DVD-ROM, and recordable or DVD-RAM. The
DVD-ROM format is fixed but there are currently four different types of DVD-RAM
on the market and in development. DVD-RAM discs can be 'naked' or sealed inside
plastic cases or 'caddies', and there is much confusion about compatibility.
The only scrap of good news is that all DVD RAM/ROM drives can read normal CD-ROMs.
The huge increase in capacity means it has a promising future, but for the
moment at least it's a good idea to wait until the dust has settled, and
there's some DVD software on the market that you actually want.
JARGON FILTER
CACHE
Part of a computer's memory set aside for storing
frequently-used data from a disc drive, speeding up the transfer of information
DRIVER
Small program that tells Windows 95 how to communicate with
a particular piece of hardware, like a disc drive, mouse, joystick or printer
RIBBON CABLE
Flat multi-way cable, used inside a PC to connect disc
drives to the main motherboard or plug-in controller cards
TOP TIP
Every so often you may want to transfer files between PCs on
floppy disc. It's no problem, providing the file is no larger than 1.4Mb. If it
is you could compress the data, or use multiple floppies, but there's another
option, compress the disc. Windows 95 (and 98) has a utility called DriveSpace.
It is intended to increase the capacity of hard disc drives, but it works just
as well with floppies, almost doubling their capacity, to around 2.6Mb. Insert
a clean disc into drive A: and from the Start Menu click on Programs, then Accessories
then System Tools and open DriveSpace. Click on the disc icon or choose
compress from the File men and follow the instructions.
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