PC Buyer Beware!

Diagnose, troubleshoot and fix RAM memory problems

The causes of RAM memory problems and how to diagnose, troubleshoot and fix them

Symptoms of RAM memory problems

Crucial DDR2 RAM memory modules that fit into keyed DIMM slots on the PC’s motherboard but only if it supports DDR2 memory

Visit the RAM Memory: DDR, DDR2, DDR3, DDR4 page of this website for detailed information on it.

Bad or faulty RAM memory

Bad or faulty RAM memory is the major cause of RAM memory problems. All kinds of very strange symptoms that appear to be brought about by other causes can be brought about by faulty memory. That is why you should buy quality memory or make sure that any computer that you buy uses quality memory. Memory that fails to pass certain quality testing, but which can still be used, is sold to computer manufacturers. It is used in budget systems. It may never be problematic but might be highly problematic.

Tracking down the cause of problems brought about by faulty or low-quality memory by a technician can be very time-consuming and expensive. Cheap low-quality memory is nearly as bad a source of  system failure as using a cheap power supply unit. Crucial, Kingston, Samsung, Corsair, etc. only sell quality memory.

Symptoms displayed by bad memory

  1. – As an installation of Windows 7/8.1/10 ages, the size of Windows itself increases due to updates, patches and hot fixes and the installed software increases, increasingly slowing the system down compared to the speed it operated at to begin with. The slow-down is most noticeable when using software that needs to have access to plenty of memory. If there is an adequate amount of free disk space on the system’s hard drive and it is defragmented, the most likely cause is insufficient RAM memory. SSD drives must not be defragmented using a defragmentation tool. Increasing the amount is the best way to improve performance. To make sure that you get the correct memory, make use of the Crucial memory-selector tools. The Crucial System Scanner is installed so that it can examine the system and suggest upgrades. The Crucial Advisor tool can be used if you know how much memory is installed and how much more can be installed.
  2.  – Random restarts, sudden freezes that require a reboot is most likely to be caused by faulty RAM and/or a faulty hard disk drive, but can also be caused by a faulty motherboard or some other faulty component. Switching a suspected faulty component with know working alternatives is often the best method of fixing such a problem.
  3. – A Blue Screen of Death (BSOD) just before the computer refuses to start up or starts up but recurs are mostly brought about by RAM and hard-drive failures.
  4. – Because memory is used to access all files via programs, bad memory cannot access them properly and therefore gives the impression that the files are corrupt when it is really the memory that is corrupt. If you attempt to install software or reinstall Windows, or any other operating system, on a system with bad memory, it will fail to install. The bad memory will slowly corrupt the system’s whole file structure until it can no longer function. To get the system back to 100% the way it was would require restoring a backup or system image that was created before the corruption by the bad memory began.

The causes of faulty RAM memory

    1. – Power surges and static electricity. To protect electronic equipment from power surges, use surge protectors, not power strips, which offer no protection. Static electricity can build up in your body. If it is discharged into memory modules that you touch it will destroy them. The voltages created by static electricity are very high – many thousands of volts – and electronic equipment cannot tolerate being hit by it. You should always earth yourself by touching metal that is earthed, such as a radiator, before touching memory modules, graphics cards, motherboards, etc. It is not necessary to use an anti-static wrist-strap when working on computer components. A vacuum cleaner can discharge static electricity, so never use one to clean a computer, use a can of compressed air instead to get rid of dust. After you have used a vacuum cleaner, your body will probably be charged with static electricity.
    2. – Excessive heat is detrimental to electronic components, including RAM memory. High-performance memory can generate heat than can be detrimental to it. Some memory modules come with attached passive heatsinks. They can also be bought and added to the modules.  The other components of a computer can create excessive heat that harms them and adjacent components. If the processor and memory are overclocked beyond their stock speeds, excessive heat can be generated, requiring additional cooling of the components themselves and the case fans.  A build up of dust inside a computer is another cause of excessive, damaging heat to build up. The image below is of a Corsair memory module with a passive heatsink fitted to it.

Corsair RAM memory module with a built-in passive heatsink

        3. – A memory module can be sound but installed in a faulty DIMM memory slot on the motherboard. Using another slot that is working fixes such a problem. The PC’s motherboard user manual provides information on which memory modules can be installed in the slots and in which configurations to achieve, dual-channel, triple-channel or quad-channel operations, which uses two, three or four memory modules as if they are a single unit. PC motherboards can have 2, 4 or 8 DIMM memory slots.

Troubleshooting RAM memory problems

Start with the easiest and progress to the more difficult and/or time-consuming troubleshooting options.

Problems caused by installing additional memory

Note well that, if you are installing additional memory, it should be made by the same manufacturer as the existing memory, because using memory made by different manufacturers can cause problems, such as freezing, Blue Sceen of Death, system reboots, etc.

If you have just installed new or additional memory that doesn’t work – is not recognised by the system – or makes the computer fail to boot, or the memory is bad, you have either installed memory that the motherboard does not support, or you have installed it in a faulty DIMM memory slot, or you have not installed it in the correct slot. Use the information in the motherboard’s user manual – made available from its manufacturer’s website in the PDF format – to find out the order in which memory must be installed in the slots. The free CPU-Z tool identifies the processor, the installed and recognised memory and the motherboard, as does the free Belarc Advisor. If you suspect that the memory is bad, make sure by testing it in another computer that supports that type of memory – DDR, DDR2, DDR3, DDR4 – if you have access to one.

BIOS/UEFI beep codes and LED codes

When a desktop PC fails to boot it can sound off a beep code via its case speaker or display a code at the back of the case on the motherboard’s ports panel or on the motherboard itself. The motherboard’s user manual will provide information on the make of the standard BIOS or UEFI BIOS. Once you have the make of BIOS – Award, Phoenix, AMI, etc. – you can conduct a web-search for the beep codes. E.g., web-search for AMI beep codes if the motherboard uses an AMI BIOS or AMI UEFI BIOS. For example, a memory problem might be indicated by one short and two long beeps and a hard-drive problem might be indicated by three short beeps. The motherboard user manual will provide information on the diagnostic codes displayed, using LEDs, by the motherboard at the back of the case or on the face of the motherboard itself.

If none of these troubleshooting methods work, the last option you can try before taking the computer into a computer repair store, is running the Windows Memory Diagnostic Tool or a third-party tool, most of which are free. Your computer manufacturer, such as Dell and HP, might also provide a set of diagnostic tools with your computer, including one that tests memory. Some useful links are provided below.

Windows Memory Diagnostic Tool

The Windows Memory Diagnostics Tool performs tests on the RAM memory of the computer it is used on. Faulty memory causes all kinds of peculiar problems that are difficult to diagnose, such as files that become corrupted.

Windows Memory Diagnostics Tool (Windows 7) –


Start Memory Diagnostic Tool in Windows 8 –


Alternatively, you can use the free MemTest86. –