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Guide to Troubleshooting memory using
BIOS Beep Codes The
BIOS on the motherboard will always perform a power-on-self-test “POST” during
power up, usually this test is perform to ensure proper system function and if
a failure occurs – the “POST” will identify the failure and emits a beeping
sound to prompt the service technician to take corrective action ASAP. The
exact meaning of the beeping codes varies from different BIOS developers, there
are 3 basic BIOS developer today, the most popular BIOS is made by “American
Mega-trend” - AMI, Award and Phoenix BIOS. The beep codes for this AMI &
Award BIOS developer are provided in this memory troubleshooter guide, we do
not provide beep code reference for Phoenix BIOS and custom BIOS written by
other companies other than the two mention. Beep
codes are not entirely consistent sometimes to detect the exact failures, but
generally it is still the most dependent methods to diagnose a fault without
opening up the PC system or using any diagnostic software Troubleshooting
Memory Failures using Award BIOS Beep Codes Award
is the another popular BIOS developer and they use the fewest beep codes by
far. Procedures –
The normal procedure is to power up the PC system, watch for error message on
the monitor screen and listen to the PC beep tone. A single beep during boot-up
process is normal and does not indicate a failure if the system continues to
boot-up. 1 Long Beep tone - Memory
Problem 1 Long Beep and 2 Short
Beeps - DRAM Parity failure 1 Long Beep and 3 Short
Beeps - Video error Continuous Beep tone -
Memory or Video memory failures My PC boots up okay but
seems to hang up after running for one hour or so. How can I find out what is
wrong? Well,
this is tricky situation. Typically you may want to begin by finding out if
it's a memory related problem. DocMemory PC Memory Diagnostic software is
designed for this very purpose. You can start by downloading a copy of the
software from DocMemory Diagnostic Site , follow the setup instructions and run
a diagnostic test on your PC memory. If
all Memory tests results returns good, you will need to isolate and examine
other possibilities such as CPU, Motherboard or other peripherals that you have
in your PC If I
have regular memory sizing error during POST (bootup), how should I trouble
shoot the failure ? A One of the most common memory problem faced in older PC
system during boot-up is “incorrect memory sizing” or the error number 164.
Sometimes failures could be caused by incorrect software setting, sometimes it
could be caused by hardware – which could be easily fixed if you know where the
faults lies. In
most cases hardware failures are caused by the natural aging process of the
memory components, defective memory module socket, dirty contacts, cold solder
joints during assembly and memory module not seated properly in the socket due
to vibration. It
is important to pay attention to intermittent memory failure, before you make
any expensive decision to replace the expensive memory - try cleaning the
memory module contacts for both old and new ram to see if the problem can be
fix: Here ‘s the How to : Things
needed – Contact Clean (Purchase from local computer hardware
store) - Cotton Bud ( For cleaning contact with) - Screwdriver (pc case
removal) - PC user manual 1 - ensure environment is
static safe by removing any unwanted plastic, bags from your workbench. Keep
the computer system plugged into your AC unit but ensure that the power switch
on the PC is turned off. Keeping the PC plugged in the AC will ensure that case
is grounded thus reducing the possibility of damaging the module or system from
ESD (Electro Static Discharge) 2 -After removing the casing
cover, ground yourself by touching any of the metal surfaces on your computer
casing. Doing this step discharges any static built up on your body and
clothing 3 - Visually locate the
computer memory expansion slots. This is normal visible but if in doubt, refer
to your operation manual instruction book. 4 – the first thing to do is
to remove the memory module and perform some visual inspection to check the
memory socket which sits the memory module. Make sure all the pins are
straight, no cracks or broken pins must be found. A
Wet the end of a cotton swab with the solvent, the swab should be wet but not
dripping B Using a circular motion, clean the contacts on the memory module. C
Allow the contact surface to dry thoroughly. D Replace the memory module into
the socket. E Repeat steps B through D for each module you have. F Power on the
computer to test the RAM. G If you see no memory errors, replace the PC's case
and power-up away. Additional Tips: 5. While contact cleaner is
preferred, it is also a well-known trick that you can also clean contacts with
a pencil eraser. 6. Continuing RAM errors are usually a sign of a bad memory
module. If cleaning the contacts doesn't solve your problem, try to isolate the
faulty module and replace it. Some
techniques for troubleshooting Memory failure without a Memory Tester. You can attempt the
following experiment- : A Removing
the modules one by one from motherboard. This is simplest method for isolating
a failing module, but this may apply only if the motherboard have more than one
module on the SIMM or DIMM Slot. By selectively removing module one at a time
from the system and then running the test you will be able to find the bad
module very quickly. Be sure to mark the module that passes or when it test
fails. Swap
the modules around . When none of the modules can be removed, swap and rotate
modules to find which module is defective. This technique can only be used if
there are two or more modules in the system. Change the location of two modules
one at a time. For
instances, place the module from SIMM slot 1 into slot 2 and place the other
module from slot 2 in slot 1. Run the diagnostic test and if either the failing
data bit or address changes, you know that one of the module you have just swap
is defective. By using several combinations of module swapping you should be
able to check which module is defective. Replacing
with known good module. If you are unable to use either of the above two
techniques, you are left to use known good modules and selectively replace of
modules one by one to pin point the memory failure. This is the easiest way to
detect memory failure. Removing
and cleaning the metal contacts. If your PC system is older, sometimes dust and
oxidation will cause poor contact in the SIMM/DIMM slot. Remove the module and
clean the gold or tin contact with a “pencil eraser” or any cleaning solution
used for video and audio head cleaning. Make sure you remember which slot is
being used, and be careful not to reverse the module while reinserting into the
SIMM/DIMM slot Identifying
memory failure using motherboard BIOS codes. If you are not trained to perform
the correct diagnostic methods – majority BIOS developers and motherboard
manufacturers have device a simple way of telling you if your system is having
problem by emitting beeping tones from the build in speaker on the motherboard,
without the aid of a memory tester. Guide
to Troubleshooting Memory Failures without a Memory Tester This
section is written with the assumption there is a general understanding of PC
operating system, in order for you to be capable of performing the diagnostic
procedures detailed below. We
will try to describe the entire process in full detail, however it is beyond
the scope of this troubleshooter guide to provide all the necessary information
to cover all possible PC system failures. For further assistance with
non-memory related failures, please consult your PC manual or manufacturer
support help online system. If your particular question is not addressed in
this section – please send us an e-mail and we will do our best to provide you
with the right answers. When you are experiencing
memory failures on your PC system, there are several faults to determined,
check the following: * PC system does not boot-up
* HIMEM.SYS does not load * Memory failure due to system hanging up, or system
rebooting after running a large program. * Fail to install win3.1, Win95 and
Win98 * Windows program is unstable * Continuous beeping sound emitted by
system during power up * Continuous ram count during boot-up , without loading
Windows program * No display other than blue screen on the monitor during
boot-up * Totally no video display on the monitor. * System hang or rebooting
after prolong usage. All
of the above are typical of memory related failures, you need to be either well
trained or PC knowledgeable to be able to perform the correct diagnostic
methods. Once
a memory failure has been detected, identifying the defective module is not an
easy task either. With a large variety of motherboard provided by different
manufacturer around the world, and with the many different combination of
SIMM/DIMM slots provided, it would be difficult if not impossible to assemble a
complete information about how a particular memory error would map to a failing
memory module. However,
there are some basic rules that may be taken to pinpoint defective modules
using a memory diagnostic software as an aid. Troubleshooting
Memory Failures using AMI BIOS Beep Codes AMI
BIOS is the most popular BIOS used by most motherboard manufacturer- you should
be able to determine your system BIOS by reading the screen display on the Top
screen during power up. Procedures –
The normal procedure is to power up the PC system, watch for error message on
the monitor screen and listen to the PC beep tone. A single beep during boot-up
process is normal and does not indicate a failure if the system continues to
boot-up. 1 Beep tone - DRAM refresh
failure 2 Beep tone - DRAM Parity
failure 3 Beep tone - Base 64K RAM
failure 4 Beep tone - System timer
error 5 Beep tone - CPU failure 6 Beep tone - Keyboard
controller error 7 Beep tone - Virtual mode
error 8 Beep tone - Display memory
read/write error 9 Beep tone - ROM BIOS
checksum error 10 Beep tone - CMOS register
read/write error 11 Beep tone - Cache memory error Continuous Beep tone - Memory or Video memory failures References: http://www.oempcworld.com/support/Guide_to_troubleshooting.htm |
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