Lesson 3: Storage Devices
I. Reading
A.
Try to
answer these questions.
1. What do
you know about the storage devices?
2. What is
the main function of a hard disk?
3. Which
unit is used to measure hard disk capacity?
4.
Can you think of one advantage
that hard disks have over floppies?
B. Read the text again and make a list of the
technical aspects that you should consider when buying a hard disk
When
buying a hard disk...
Hard disks have important
advantages over floppy disks: they spin at a higher speed, so you can store,
and retrieve information much faster than with floppies. They can also hold
vast amounts of information, from 500 MB up to several gigabytes. Apart from
this, both types of disks work in the same way. To directly access the
necessary information, the read/write heads of rigid disks seek the required
tracks and sectors, and then transfer the information to the main memory of the
computer or to another form of storage, all of which is done in a few
milliseconds (ms).
Bearing in mind that you always need disk storage, it
is good sense to ask yourself some vital questions: What size capacity do I
need? What speed can I use? What kind of storage device is the most suitable
for my requirements? If you only use word- processing programs, you will need
less storage capacity than if you use CAD,
sound and animation programs. For most users, 2 GB on the hard disk is enough.
Now let's turn our attention to speed. Access times
vary from 8 ms to 20 ms. 'Access time' -or seek time - is the time it takes
your read/write heads to find any particular record. You have to distinguish
clearly between seek time (e.g. 20 ms) and 'data transfer rate' (the average
speed required to transmit data from a disk system to the RAM, e.g. at 20
megabits per second). Remember that the transfer rate also depends on the power
of your computer.
Task 1: Now read these sentences and decide if they
are true (T) or false (F)
1. Hard
disks use rigid rotating disks.
2. 'Seek
time' refers to the average time required for the recording heads to move and
access data.
3.
If you use multimedia
applications, you need the same storage capacity as required for word
processors.
4. 'Access
time' and 'data transfer rate' mean the same.
5. Optical
disks are magnetic.
6. Each Jaz
cartridge can hold up to 1,000 MB of data
7. CD-ROM
disks are used for storage of massive amounts of information.
Task 2: Complete the
advertisement for the Mega Mind hard disk with the words in the box.
Megabytes
|
drive
|
compatible
|
highest
|
time
|
protection
|
secure
|
write
|
multimedia
|
|
|
|
|
|
|
Mega Mind XT
|
|
Today's personal computers are very powerful, but
to handle large applications like databases, (1) …… DTP(desktop publishing) and
CAD, you need to have more than 200 (2)… in your hard
disk. That's where Mega Mind XT comes in: a reliable hard (3) ..........with 6 gigabytes of
capacity; 8 ms average seek (4)…………. and 13 mbits/sec average data transfer
rate; and a drive
unit with a five-year warranty.
You also
receive software utilities that let you easily manage and (5) …..your data. Our software
provides formatting, partitions, disk optimization, and password (6) ……..Mega
Mind XT is
(7)……. with IBM PCs as well as Macintosh computers. As with every Mega Mind product -
hard disk or optical, 1 GB to 6 GB -the XT gives you the (8)……...performance.
So call us today on (0181)796 0402. Or (9)….. to Mega Mind, PO Box 673, London,
N22 1 XB.
II. Speaking
How can I prevent users from connecting to a USB
storage device?
To prevent users from connecting to USB storage devices, use one or more
of the following procedures.
If a USB storage device is already installed on the
computer
If a USB storage device is already installed on the computer, you can
change the registry to make sure that the device does not work when the user
connects to the computer. To have us fix this problem for you, go to the “Fix it for me”
section. If you would rather fix this problem yourself, go to the “Let me fix it myself”
section.
Fix it
for me
To fix this problem automatically, click the Fix this problem link. Then, click Run in the File Download dialog box, and follow the
steps in this wizard.
Note: if you are not on the computer that has the problem, save the Fix it
solution to a flash drive or a CD
and then run it on the computer that has the problem.
Let me fix it myself
If a USB storage device is already installed on the computer, set the Start value in the following registry
key to 4: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\UsbStor
When you do this, the USB storage device does not work when the user
connects the device to the computer. To set the Start value, follow these steps: (Rearrange the steps in the correct order)
1. Click Start, and then click Run.
2. Locate and
then click the following registry key:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\UsbStor
3. Exit
Registry Editor
4.
In the Value data box, type 4,
click Hexadecimal (if it is not
already selected), and then click OK.
5. .In the Open box, type regedit,
and then click OK.
In
the details pane, double-click Start