How to diagnose bad RAM

Does your computer emit endless beeps during bootup? Does your PC crash for no apparent reason at random intervals? Or you get blue screens of death with errors such as IRQL_Less_or_Not_Equal? If so, then it is very likely that there is a problem with your computers memory (RAM).

Common symptoms of bad ram

There are many indicators of bad memory, but the most common ones are:

  • Computer not booting at all, beeping endlessly. When this happens all you can do is replace the RAM by trying another stick. You wont be able to use any ram diagnostic software in this instance.
  • Distorted graphics on the screen. However it is possible this can be video card related.
  • Blue screens of death during the installation of Windows XP or Windows 2000. This is an obvious sign of faulty RAM.
  • Crashes or blue screens during normal operation of the system (emails, web surfing etc.)
  • Crashes during memory intensive tasks such as using Photoshop, playing 3d games etc..

Testing bad RAM with Memtest86+:

Memtest86+ is a ram diagnostic tool that is bootable from a floppy disk or a CD. There are two modes that Memtest86+ is able to run in which are basic mode and advanced mode. Advanced mode takes considerably longer to test so basic mode should be sufficient to find any major problems with your RAM.

To use Memtest86+, download the floppy version, unzip it and run the executable (you will need a blank floppy for this) or download the bootable ISO CD version which you can burn to a CD using a CD-authoring program like Nero.

Restart your computer with either the floppy or CD version in the drive to start the program and it will automatically start a basic test.

Any errors that appear will show at the bottom of the screen.

What to do if you have bad RAM:

Once you have determined that you have some bad ram using Memtest86+ you will want to return the RAM to the store or manufacturer and get a warranty replacement. However, you need to know which RAM stick is failing because many computers have multiple sticks of RAM in them.

If you only have one stick of RAM:

If you have only one stick of RAM, the first thing you should do is move the stick of ram to another slot on your motherboard as there is a possibility that the slot could have problems such as a bad contact between the motherboard and the RAM.

To move the RAM, first turn off the computer and unplug the power cord. Open up the computer case and unclip the two retention levers and remove it from its slot.

Insert the RAM module into another slot, push it down firmly and the two retention levers should snap into place. If they don’t then you probably are putting the RAM in the wrong way around.

Once this is done, plug the power cord back in and start up your computer again with the Memtest86+ disk in it and retest. If you still get errors then it is most likely that you have a faulty RAM module and it should be replaced.

If you have multiple sticks of RAM:

If you just installed a new stick of RAM and you are getting errors, then common sense points to the obvious culprit.

If you have more then one stick of RAM and you are getting errors then you need to determine which stick of RAM is causing the problem.

Following similar steps as above for the single sticks of RAM, power down the computer, open up the case and remove all but one stick of RAM and retest. Test each RAM stick in the same motherboard slot and if you get an error with just one of them then you have found the failing stick of RAM.

If they all fail in the same slot, it is possible that the slot is failing and you should try another RAM slot. If they all have no errors in the same slot then it is most likely another RAM slot on the motherboard that is failing and you should test all the RAM sticks again in the other slot.

Bryce Whitty

About the Author

Bryce Whitty
More articles by me...
Bryce is an Australian computer technician and the founder of Technibble. He started his computer repair business when he was 17 years old and is still running it 9 years later. He is an avid traveller and spends at least a month of the year in another country.

Comments (15)

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  • MATT says:


  • gang says:

    this is nicely written hope it helps me

  • dk says:

    thanks the guide was great my computer is sorted 10/10 cheers.

  • Al says:

    My computer is showing all the errors stated in this article (except distorted graphics). However, when I ran memtest86+, it didnt detect any problems. (I let it scan twice)
    Right now I just took out 2 x 512mb Ram and a 1gb ram out. I’m only using 1gb, no errors so far.

  • adam A says:

    my computer has a lot of trouble booting but it does not make beeps do you still think it is my ram?

  • ethan says:

    my acer aspire 4736g laptop is 4gb ram,
    2gb kingston and 2gb samsung so different brand is ok..? blue screen problem thn check is kingston ram problem, exchanged thn few month oso same problem …so wat going on…?
    is compatible..?

  • Bob says:

    This is an opportunity for software programmers to make a Live memtest that runs through windows or something. Memtest took me 7 hours last night then crashed before it finished. what a waste of time. it reported over 1000 errors and i dont know which of my 4 dimms has the problem. so.. should i run and wait for another crash? :(

  • Reid says:


    Just do like the article says and remove all but one and then see if that runs fine. Do this for all the sticks until you see your error.

  • Gabby says:

    I switched my memory sticks in all possible combinations. I keep getting the same errors when I switch them?

  • krishan says:

    hey i get a driver iqrl less or ot equal screen on my compaq presario cq60 windows vista home primuim latopn ive had it for nealy a year and whenevey i play a game or turn onn the screen relolution rtets to`self and when u open more then 4 tabs with flash n atuff ike that the blue screen comes up
    i have a dual core amd turion and a nivida ge force someting grpghics cars and am about to run memtest 86

  • irfan says:

    hi thanks for help

  • Sagar says:

    for past few days my pc suddenly shuts down after few hours i use pc,
    i think there is problem with my ram
    have 2 256mb ddr2 ram sticks. when irun memtest on them individually and in different slots. there are no errors. however on using both of them simultaneously pc wont start

  • Kristian says:

    The program won’t work because my OS is 64-bit. Is there another version of the program that works with my OS?