Aside from trying to find an intermitt DRAM error on a motherboard (main board), troubleshooting memory problems can be one of the most difficult diagnostic issues you may face when trying to figure out why a computer begins doing things that it shouldn't be doing, or for that matter, not doing what it should. Understand that these troubleshooting techniques are not to be misconstrued as a replacement for a thorough diagnostic inspection of your PC by a fully qualified technician.

On the contrary, these techniques should only be used by those who are reasonably familiar with computer components and have an immediate need to get their computer back up and operational to finish a task or safeguard data before taking the computer to a qualified technician for service. I take no responsibility of any type with respect to any person following the procedures and techniques outlined herein. By following these techniques or procedures, you acknowledge that they were provided to assist you with an emergent problem and that you are performing them solely and completely at your own risk!

First some Do's and Don'ts!

The Do's

    *Make sure that your work space provides sufficient room for you to work on the computer without allot of clutter.
    *Your work area should also have enough room to place tools where you can reach them as well as enough room for any components you may need to remove.
    * Make sure the work space is well illuminated.
    *Make sure that you have all of the tools you need to do the job correctly before you start. We have provided a list of the basics below.
    *Here's a list of things you will need: (or should have)
          o Small Flat bladed Screw Driver
          o Small to Medium Sized Phillips Screw Driver
          o Cotton Swabs and/or Q-Tips (electronics stores have stick type Q-Tips that work!)
          o Clean Red School Eraser
          o Contact Cleaner (VCR Head Cleaner or Rubbing Alcohol will work! Any non-residue leaving Solvent)
          o Clean Cloth (old T-Shirt would be great)
          o Small Can of Compressed Air (This can be purchased at most electronics stores)
          o Small Flashlight
          o Anti-Static Wrist Strap
          o One Jumper wire 3' long with alligator clips on both ends
          o MS-DOS Boot Disk (you can download one by clicking here)

    * Why all of these things? Simple, you will need the screw drivers to open the case as well as possibly moving components out of the way. You will need the Q-Tips and cloth to clean surfaces with the contact cleaner, including the contact edges of the memory modules. The cloth will enable you to clean contacts without touching them with your fingers. Oils from your skin can damage contacts and cause shorts. The compressed air is used to blow out dust and debris found in the case when you open it. The reason for the flashlight should be obvious. Static electricity is a major problem when working on any type of electronics, and even more so with computers. A static electricity discharge can rendered many of your computer components such as the motherboard, CPU and memory useless. An anti-static wrist strap will prevent you from transmitting static electricity from your body and clothes to you PC. A Jumper wire is good to ground your PC to the house ground. The small screw that holds the receptacle cover plate on at the wall is grounded! Lastly, many memory diagnostics need to be done at the DOS level rather than within any of the Windows interfaces, therefore a MS-DOS boot disk is helpful to have (You can find one at www bootdisk com). Someday ill edit this when i have time to write, making a boot disk.
                                                                    
The Don'ts

    *Don't place any plastic covering of any type on your work space, and make sure there are no plastic bags, sheeting or coverings near the computer. Plastic transmits static electricity!
    *Don't ever work on a PC unless you have first grounded yourself. A wrist anti-static strap is best, but if one is not available, touch the outside metal PC case before touching any electrical components. Extremely dry environments create static electricity, as do certain types of carpet when you walk across them.
    *Don't ever work on a PC that is still plugged into its power source. Always unplug the PC before you you even begin to remove the cover.
    *Don't ever touch the contact edges of electronic components. Human skin oils are acidic which can cause deterioration of the contacts.
    *Don't work on a PC without having the correct tools. You wouldn't conduct brain surgery with carpenter tools would you?
    * Don't force anything. If you have to force it, you're doing it wrong!

Where to start:

    First, don't panic! Try and approach the problem logically, as difficult as that may be to do. Generally, memory problems can be placed into two broad categories.

Category 1: (see below)

    Your computer has been acting normally until this problem arose:
        You haven't added or changed any hardware.
        There may have been a brown out, power outage or a possible lightening strike to a local power line or telephone line near or at your home or place of business.
        Someone may have improperly shut off the computer, or you may have had internal electrical problems in your home or business.
        A virus or two may have invaded your computer.
        Your computer is five or more years old and has never had the case opened or the interior cleaned and inspected.

Category 2: (see below)

    Your computer has not been acting normally since you:
        Purchased it.
        Added or changed memory.
        Added new hardware items internally to the computer.
        Added new hardware items externally to the computer.
        Added new software.

Troubleshooting Category 1 Memory Problems

If you haven't added any new hardware, and you haven't made any changes to the existing hardware (e.g. you haven't been inside the PC case for any reason), this narrows the possibilities considerably.

You suspect the problem resulted from an external source:

If you suspect that your computer, or any of its components, may have been damaged as the result of a brown-out, power surge or spike (power pulse in excess of the normal power line voltage), a lightening strike to a power or telephone line in the neighborhood or directly at your location, we recommend that you proceed no further and make arrangements to have you PC inspected by a competent professional. If you have insurance, you may also want to contact your insurance representative.

If you had a storm recently and your computer is not booting up and its just "Frozen" and wont even get to the windows screen anymore or any screen for that matter, then try this diagnosis. Does your computer have a modem that you still use to connect to the internet? Chances are that the telephone line was stiff plugged in, cause for some reason in a storm everyone runs and unplugs the computer, but lightening strikes don't zap computers through the wall socket cause houses are usually well grounded, where it comes in from is the telephone line and commonly just by removing the side panal and removing the modem ( its the component the phone cord plugs into in the back of your computer, NOT the ethernet card, which looks like a FAT phone line would go there, thats for DSL and CABLE internet connections. Bigger cable, faster connection.) Removing this after a lightening storm often times will cure the problem if lightening has zpped you through the phone line as it normally doesn't do anymore damage than that. And that $10 modem you can find here on ebay and change out yourself will save you a  $150 trip to a computer technician like myself.

Someone accidentally unplugged the computer, or there was a momentary loss of power:
If the power problem you experienced is limited to that of someone accidentally unplugging the computer, or just a momentary loss of power, and the memory problem suddenly appeared, then the following may help you diagnose the cause.

    *The sudden loss of power may have been enough to trigger a problem with a failing memory module. To attempt to diagnose this, you may want to clean the inside of the computer to remove dust and debris and then clean the individual memory modules as noted below.

    *A sudden loss of power may have altered the software BIOS code in the BIOS chip on your PC's motherboard. To resolve this, you can try clearing the BIOS settings first, and if that doesn't work, then it may be wise to take the PC to a technician.

    *There are two ways to attempt to clear the BIOS settings and reload the default code. One is to boot the PC into the BIOS setup and use the "set defaults" option in the BIOS. setting experienced, the second method would be to force the BIOS into a reset by moving a "clear BIOS" jumper on the motherboard. Either of these methods require that you have the manual for you motherboard.
   
    *If clearing the BIOS doesn't work, you may need to open the case, blow out the dust and accumulated debris (or vacuum it out, although this rarely works) and then clean the memory modules as noted below.

A virus or two may have infected your computer:
While it is possible that a virus has infected your system by altering the BIOS code used by your motherboard, that possibility today is extremely rare. Most computer produced over the last 5-6 years use motherboards with BIOS chips that incorporate a BIOS block. This block prevents anything from being written to the BIOS unless it results from a special program written by the BIOS developer. But, it is possible!

If you feel that this is a real possibility and (A) have excluded all other possibilities and (B) you are not using any form of anti-virus software, we recommend that you stop here, purchase the anti-virus software you need and then make certain that your PC is virus free.

Your PC is 3 to 6 years old and has never had the case opened and the interior cleaned and inspected:
If the memory failure is intermittent, (happens randomly), you may want to try a thorough cleaning before deciding to replace the memory modules. This can be done relatively quickly and will usually will eliminate dirt, dust and other debris as the cause of your problem.

Here's how, along with a list of the very minimum things you will need:
    * Can of compressed air  (Purchase from local computer hardware store)
    * Contact Clean (Purchase from local computer hardware store)
    * Cotton Bud or Q-Tip (For cleaning with Contact Clean)
    * Small piece of cotton cloth (an old T-shirt will do)
    * Screwdriver (pc case removal)
    * PC users manual

   1. Insure that your environment is static free by removing any unwanted plastic from in and around your workbench.
   2. Unplug the computer system from its AC source, and (if possible) attach a ground wire to the ground screw in between the two sockets. This insures that case is still grounded, thus reducing the risk of damage to the module or system from ESD (Electro Static Discharge).
   3. After removing the case cover, ground yourself by touching any of the metal surfaces on your computer case. This step discharges any static built up on your body and clothing.
   4. Visually locate the computer memory expansion slots. This is normally visible but if in doubt, refer to your PC's operation manual.
   5. Next, remove the memory modules and visually inspect them and the memory sockets. Make sure all the edge pins are straight, and there are no cracks, gouges, broken pins or other signs of damage. You may want to note the way the modules were installed so that you can reinstall them later.
   6. Wet the end of a cotton swab with the solvent, the swab should be wet but not dripping, and using a circular motion, clean the contacts on the memory module.
   7. Next, use the cotton cloth to wipe away any fuzz from the cotton as well as any remaining cleaning liquid and then allow the surface of the contacts to dry thoroughly.
   8. Replace the memory module into the socket carefully.
   9. Repeat steps 5 through 8 for each module you have.
  10. Place a boot floppy into the floppy drive to prevent booting the operating system on the hard drive and then power on the computer to test the RAM. If there are no memory errors, shutdown, replace the PC's case and power-up.

Additional Tips:

    * While using contact cleaner is the preferred method, in an emergency you can clean the contacts with a pencil eraser. Just wipe the contacts thoroughly with a clean cotton cloth (T-shirt) dampened with some nail polish remover before putting them back.
    * Continuous 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.

If none of the above procedures have worked for you, then it's rather obvious that the problems are more serious and require additional diagnostic methods and possibly some diagnostic software testing.

The next series of methods and procedures will take you deeper into memory testing techniques that you can use to resolve a possible memory problem. You are reminded of the fact that these are suggestions only, and do not represent a comprehensive diagnostic of your computers memory. If you feel that any of the suggested methods and techniques re beyond the scope of your ability, then you may want to seek the assistance of a qualified technician.

Troubleshooting Category 2 Memory

Troubleshooting what we refer to as Category 2 memory errors is decidedly more difficult as there are many more factors to consider in order to determine a cause. Our approach to defining a cause for a Category 2 memory error is different from one that we would follow if the computer were sitting on our diagnostic bench. Remember that this is a broad based diagnostic approach designed for the Internet to give you the ability to sift through as many reasons or causes for these errors as possible while at the same time eliminating those possibilities that someone may have suggested that have no relevance.

You have been experiencing memory error problems with your computer from the day you received it:
We have been receiving an increasing number of calls for help to sort out memory problems with new computers, especially those that fall into the low-end mass produced class. Although it provides you with very little consolation, you must remember that mass producers do not install module that cost $75 to $100 in systems they sell for $1,000 or less. If you have purchased a new computer and have been having memory related problems, it is most probably due to one of three reasons, a poor quality or failing memory module, a physical problem with the motherboard or a setting or jumper on that motherboard or there is a problem with a BIOS setting. You can attempt to reset the BIOS to rule that out as a possibility, but as for the other possibilities, we recommend that you contact the manufacturer and have them examine the system.

You have added memory or changed the memory modules and now you're experiencing memory errors:
This type of memory problem occurs all too frequently. Here is a short list of the possible causes:
 
*If you have added memory modules to those already in your computer, make sure that the new modules exactly match the type you already have. Mismatched memory modules occur frequently. In theory you should be able to install PC 66, PC 100 and PC 133 memory, however we have found more often than not that this does not work.
  
 *If you computer requires PC 133 memory and you have added memory and a memory problem has arisen, in all probability the new modules are not PC 133 qualified. This is also true for PC 100 memory modules. All too frequently some resellers offer memory modules that are supposed to PC 100 or PC 133 qualified and they are borderline at best. If you need more information about PC 100 or PC 133 standards,research the following terms: PC 133 Compliant Memory. or PC 100 Compliant Memory

    *If you have replaced all of your computers memory modules and now you are receiving memory errors, there are several possibilities.
          oThe memory modules you have installed are not supported by the motherboard in your computer. You will need to either review the manual for your computer or its motherboard, or contact the manufacturer, in order to determine whether the memory modules you have purchased are supported by the motherboard. If they are not, you will need to exchange them. If they are, then you will need to check the motherboards BIOS settings. NOTE: Some computers support the use of modules that use ECC (Error Correcting Code) and some do not. This is one of the first places to check!
          o The BIOS settings on your motherboard are incorrect for the type or amount of memory installed. This is always a possibility when old modules are replaced with new. There are two ways to handle this possibility. One is to boot the PC into the BIOS setup and use the "set defaults" option in the BIOS. If the damage is minimal the BIOS can be reset in this way. If you can't get into the BIOS setup because the problem being experienced, the second method would be to force the BIOS into a reset by moving a "clear BIOS" jumper on the motherboard. Either of these methods require that you have the manual for you motherboard.

          o One or more of the memory modules is defective. Although this is an extremely rare possibility, it does happen. We purchase thousands of modules annually, and we have had this occur more than once, which is the reason that i test every component going into a system we build. If you have purchased more than one memory module, remove all but one and test your system with a single module. If the error persists, then swap the module with another and test again.
          o The modules you purchased are mismatched. This is as rare as receiving a new, but defective, module. Compare the modules completely to insure that they are identical. If they are, then you will need to dig deeper.

You have added new components "internally" to your computer (other than memory) and now you are receiving memory errors:
This does happen occasionally, and generally it is because we have overlooked something obvious such as disturbing a memory module or other internal component. Here's a short list of things to check and others to ignore.

    * First, adding or replacing a floppy drive will not cause a memory error. Adding or replacing hard drives, CD ROM drives, CD ROM burners, SCSI controllers, SCSI drives, sound or video cards will not cause a memory error.

    * If you have replaced the motherboard but are using your original memory modules, then check the motherboard manual to determine the memory types the motherboard supports. Compare this information against your actual memory modules. As an example, if your motherboard requires PC 133 qualified memory, do not attempt to use PC 100 SDRAM or EDO memory unless you know for a fact that the motherboard supports either of them. Another possibility when replacing the motherboard is the correct BIOS settings for the memory being used. Boot into the BIOS setup and verify the settings. You may need to reset the BIOS and then correct the settings.

    * It is possible that you may have unintentionally moved something, disturbed or jarred it loose or even caused something to drop onto the motherboard that is causing a short circuit. Check every connection inside the computer and make certain everything is connected properly. Presuming that the computer is laying on its side, verify that there are no screws, wires or debris of any kind laying on the motherboard that may cause a short circuit.

    * Verify that you have inserted the memory modules correctly and that they are fully seated in their slots and the locks are in place. If you are uncertain as to whether or not you have installed the modules correctly, remove the modules and reseat them. If you are having any difficulty, view my  Changing Memory Modules Guide .

You have added new "external" components to your computer, and now you are receiving memory errors:
Presuming that you have not changed anything inside of your computers case, including the installation of any add-in cards or other devices to support and external device, there are no external components that should be the cause of a memory error or failure. The addition of external devices such as printers, drives, scanners etc will not cause a memory error.

Let's distinguish between a memory error on startup or boot from that of a Windows error message when Windows is started. It is always possible that you could load software, including drivers, to support an external device such as a printer, scanner, external hard drive, tape drive, CD ROM drive or CD-R/CD-RW drive that may cause an error in one of the Windows operating systems, including a general protection fault (GPF). However this is not a memory error! If you are getting a true hard memory error during the initial start of your computer, it is purely coincidental and has nothing to do with the externally attached device.

You have added new software and now you are receiving a memory error:

As we noted in the previous comment, you will need to distinguish between a memory error on startup or boot from that of a Windows error message when Windows is started. It is always possible that you could load software, including drivers, that may cause an error in one of the Windows operating systems, including a general protection fault (GPF). However this is not a memory error!

If none of the above procedures have worked for you, then it's rather obvious that the problems are more serious and require additional diagnostic methods and possibly some diagnostic software testing.

The next series of methods and procedures will take you deeper into memory testing techniques that you can use to resolve a possible memory problem. You are reminded of the fact that these are suggestions only, and do not represent a comprehensive diagnostic of your computers memory. If you feel that any of these suggested methods and techniques are beyond the scope of your ability, then you may want to seek the assistance of a qualified technician.