10 reasons why PCs crash U must Know!!! - Pallav

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.



- by pallav...!