10 reasons why PCs crash U must Know:
Fatal error: the system has become
unstable or is busy," it says. "Enter to return to Windows or press
Control-Alt-Delete to restart your computer. If you do this you will
lose any unsaved information in all open applications."
You
have just been struck by the Blue Screen of Death. Anyone who uses Mcft
Windows will be familiar with this. What can you do? More importantly,
how can you prevent it happening?
1 Hardware conflict:
The
number one reason why Windows crashes is hardware conflict. Each
hardware device communicates to other devices through an interrupt
request channel (IRQ). These are supposed to be unique for each device.
For
example, a printer usually connects internally on IRQ 7. The keyboard
usually uses IRQ 1 and the floppy disk drive IRQ 6. Each device will try
to hog a single IRQ for itself.
If there are a lot of
devices, or if they are not installed properly, two of them may end up
sharing the same IRQ number. When the user tries to use both devices at
the same time, a crash can happen. The way to check if your computer has
a hardware conflict is through the following route:
* Start-Settings-Control Panel-System-Device Manager.
Often
if a device has a problem a yellow '!' appears next to its description
in the Device Manager. Highlight Computer (in the Device Manager) and
press Properties to see the IRQ numbers used by your computer. If the
IRQ number appears twice, two devices may be using it.
Sometimes
a device might share an IRQ with something described as 'IRQ holder for
PCI steering'. This can be ignored. The best way to fix this problem is
to remove the problem device and reinstall it.
Sometimes
you may have to find more recent drivers on the internet to make the
device function properly. A good resource is www.driverguide.com. If the
device is a soundcard, or a modem, it can often be fixed by moving it
to a different slot on the motherboard (be careful about opening your
computer, as you may void the warranty).
When working
inside a computer you should switch it off, unplug the mains lead and
touch an unpainted metal surface to discharge any static electricity.
To
be fair to Mcft, the problem with IRQ numbers is not of its making. It
is a legacy problem going back to the first PC designs using the IBM
8086 chip. Initially there were only eight IRQs. Today there are 16 IRQs
in a PC. It is easy to run out of them. There are plans to increase the
number of IRQs in future designs.
2 Bad Ram:
Ram
(random-access memory) problems might bring on the blue screen of death
with a message saying Fatal Exception Error. A fatal error indicates a
serious hardware problem. Sometimes it may mean a part is damaged and
will need replacing.
But a fatal error caused by Ram
might be caused by a mismatch of chips. For example, mixing
70-nanosecond (70ns) Ram with 60ns Ram will usually force the computer
to run all the Ram at the slower speed. This will often crash the
machine if the Ram is overworked.
One way around this
problem is to enter the BIOS settings and increase the wait state of the
Ram. This can make it more stable. Another way to troubleshoot a
suspected Ram problem is to rearrange the Ram chips on the motherboard,
or take some of them out. Then try to repeat the circumstances that
caused the crash. When handling Ram try not to touch the gold
connections, as they can be easily damaged.
Parity
error messages also refer to Ram. Modern Ram chips are either parity
(ECC) or non parity (non-ECC). It is best not to mix the two types, as
this can be a cause of trouble.
EMM386 error messages
refer to memory problems but may not be connected to bad Ram. This may
be due to free memory problems often linked to old Dos-based programmes.
3 BIOS settings:
Every
motherboard is supplied with a range of chipset settings that are
decided in the factory. A common way to access these settings is to
press the F2 or delete button during the first few seconds of a boot-up.
Once
inside the BIOS, great care should be taken. It is a good idea to write
down on a piece of paper all the settings that appear on the screen.
That way, if you change something and the computer becomes more
unstable, you will know what settings to revert to.
A
common BIOS error concerns the CAS latency. This refers to the Ram.
Older EDO (extended data out) Ram has a CAS latency of 3. Newer SDRam
has a CAS latency of 2. Setting the wrong figure can cause the Ram to
lock up and freeze the computer's display.
Mcft Windows
is better at allocating IRQ numbers than any BIOS. If possible set the
IRQ numbers to Auto in the BIOS. This will allow Windows to allocate the
IRQ numbers (make sure the BIOS setting for Plug and Play OS is
switched to 'yes' to allow Windows to do this.).
4 Hard disk drives:
After
a few weeks, the information on a hard disk drive starts to become
piecemeal or fragmented. It is a good idea to defragment the hard disk
every week or so, to prevent the disk from causing a screen freeze. Go
to
* Start-Programs-Accessories-System Tools-Disk Defragmenter
This
will start the procedure. You will be unable to write data to the hard
drive (to save it) while the disk is defragmenting, so it is a good idea
to schedule the procedure for a period of inactivity using the Task
Scheduler.
The Task Scheduler should be one of the small icons on the bottom right of the Windows opening page (the desktop).
Some
lockups and screen freezes caused by hard disk problems can be solved
by reducing the read-ahead optimisation. This can be adjusted by going
to
* Start-Settings-Control Panel-System Icon-Performance-File System-Hard Disk.
Hard
disks will slow down and crash if they are too full. Do some
housekeeping on your hard drive every few months and free some space on
it. Open the Windows folder on the C drive and find the Temporary
Internet Files folder. Deleting the contents (not the folder) can free a
lot of space.
Empty the Recycle Bin every week to free
more space. Hard disk drives should be scanned every week for errors or
bad sectors. Go to
* Start-Programs-Accessories-System Tools-ScanDisk
Otherwise assign the Task Scheduler to perform this operation at night when the computer is not in use.
5 Fatal OE exceptions and VXD errors:
Fatal OE exception errors and VXD errors are often caused by video card problems.
These can often be resolved easily by reducing the resolution of the video display. Go to
* Start-Settings-Control Panel-Display-Settings
Here
you should slide the screen area bar to the left. Take a look at the
colour settings on the left of that window. For most desktops, high
colour 16-bit depth is adequate.
If the screen freezes
or you experience system lockups it might be due to the video card. Make
sure it does not have a hardware conflict. Go to
* Start-Settings-Control Panel-System-Device Manager
Here,
select the + beside Display Adapter. A line of text describing your
video card should appear. Select it (make it blue) and press properties.
Then select Resources and select each line in the window. Look for a
message that says No Conflicts.
If you have video card
hardware conflict, you will see it here. Be careful at this point and
make a note of everything you do in case you make things worse.
The
way to resolve a hardware conflict is to uncheck the Use Automatic
Settings box and hit the Change Settings button. You are searching for a
setting that will display a No Conflicts message.
Another useful way to resolve video problems is to go to
* Start-Settings-Control Panel-System-Performance-Graphics
Here
you should move the Hardware Acceleration slider to the left. As ever,
the most common cause of problems relating to graphics cards is old or
faulty drivers (a driver is a small piece of software used by a computer
to communicate with a device).
Look up your video card's manufacturer on the internet and search for the most recent drivers for it.
6 Viruses:
Often
the first sign of a virus infection is instability. Some viruses erase
the boot sector of a hard drive, making it impossible to start. This is
why it is a good idea to create a Windows start-up disk. Go to
* Start-Settings-Control Panel-Add/Remove Programs
Here, look for the Start Up Disk tab. Virus protection requires constant vigilance.
A
virus scanner requires a list of virus signatures in order to be able
to identify viruses. These signatures are stored in a DAT file. DAT
files should be updated weekly from the website of your antivirus
software manufacturer.
An excellent antivirus programme
is McAfee VirusScan by Network Associates ( www.nai.com). Another is
Norton AntiVirus 2000, made by Symantec ( www.symantec.com).
7 Printers:
The action of sending a document to print creates a bigger file, often called a postscript file.
Printers
have only a small amount of memory, called a buffer. This can be easily
overloaded. Printing a document also uses a considerable amount of CPU
power. This will also slow down the computer's performance.
If
the printer is trying to print unusual characters, these might not be
recognised, and can crash the computer. Sometimes printers will not
recover from a crash because of confusion in the buffer. A good way to
clear the buffer is to unplug the printer for ten seconds. Booting up
from a powerless state, also called a cold boot, will restore the
printer's default settings and you may be able to carry on.
8 Software:
A
common cause of computer crash is faulty or badly-installed software.
Often the problem can be cured by uninstalling the software and then
reinstalling it. Use Norton Uninstall or Uninstall Shield to remove an
application from your system properly. This will also remove references
to the programme in the System Registry and leaves the way clear for a
completely fresh copy.
The System Registry can be
corrupted by old references to obsolete software that you thought was
uninstalled. Use Reg Cleaner by Jouni Vuorio to clean up the System
Registry and remove obsolete entries. It works on Windows 95, Windows
98, Windows 98 SE (Second Edition), Windows Millennium Edition (ME), NT4
and Windows 2000.
Read the instructions and use it
carefully so you don't do permanent damage to the Registry. If the
Registry is damaged you will have to reinstall your operating system.
Reg Cleaner can be obtained from www.jv16.org
Often a
Windows problem can be resolved by entering Safe Mode. This can be done
during start-up. When you see the message "Starting Windows" press F4.
This should take you into Safe Mode.
Safe Mode loads a minimum of drivers. It allows you to find and fix problems that prevent Windows from loading properly.
Sometimes
installing Windows is difficult because of unsuitable BIOS settings. If
you keep getting SUWIN error messages (Windows setup) during the
Windows installation, then try entering the BIOS and disabling the CPU
internal cache. Try to disable the Level 2 (L2) cache if that doesn't
work.
Remember to restore all the BIOS settings back to their former settings following installation.
9 Overheating:
Central
processing units (CPUs) are usually equipped with fans to keep them
cool. If the fan fails or if the CPU gets old it may start to overheat
and generate a particular kind of error called a kernel error. This is a
common problem in chips that have been overclocked to operate at higher
speeds than they are supposed to.
One remedy is to get
a bigger better fan and install it on top of the CPU. Specialist
cooling fans/heatsinks are available from www.computernerd.com or
www.coolit.com
CPU problems can often be fixed by
disabling the CPU internal cache in the BIOS. This will make the machine
run more slowly, but it should also be more stable.
10 Power supply problems:
With
all the new construction going on around the country the steady supply
of electricity has become disrupted. A power surge or spike can crash a
computer as easily as a power cut.
If this has become a
nuisance for you then consider buying a uninterrupted power supply
(UPS). This will give you a clean power supply when there is
electricity, and it will give you a few minutes to perform a controlled
shutdown in case of a power cut.
It is a good investment if your data are critical, because a power cut will cause any unsaved data to be lost.
