Haphazard problems are rarely easy to troubleshoot. However, the more bizarre, inconsistent/random they are, the more likely the issue is memory related.
If a machine boots, it doesn’t always mean that the memory isn’t causing a problem. There can be certain sections of memory that are bad but don’t cause a problem until those areas are used and aren’t always used by the same software. This can lead to seemingly random problems without any perceptible cause where most other hardware issues have a direct cause/effect relationship that is easy to see.
Some symptoms of bad memory include:
- Intermittent system crashes that don’t seem related, sometimes you’ll open a word document, and get a BSOD (Blue Screen Of Death), other times it may take 3 boots to get to a desktop on your computer. The computer might go days without any issues, and opening a web browser may give you a BSOD, the trickiest part about bad memory is it’s hard to pin down.
- Inability to boot
- Graphical errors, especially on systems with onboard video or discreet cards that share system memory
There are many tools available to help you diagnose memory problems. One of the most common is memtest86+, this utility performs test operations on all available memory making sure that data written to and read from memory comes out as expected. If not, an error is reported. The easiest way to get this utility to go to the site, download the ISO and use it to create a bootable CD. Reboot your computer, and make sure it boots from CD. Once the computer boots to the disc, it will automatically start checking your memory. Any red lines that appear during the check mean memory errors are present.
If your memory fails the test, you need to perform a process of elimination to figure which (if any) of the memory modules are the cause or if you have another issue representing itself as a memory problem.
The easiest way to do this is to test a single memory module at a time and see if all modules have issues or just one (for machines with more than one module). It is unlikely that you have 2 bad memory modules in a machine, so if you have more than one memory module with issues you may have a motherboard problem. On desktops, you can typically see erupted/bulging capacitors on the board indicating failure.
It is also important to realize that no hardware diagnostic software is 100%. Sometimes failures occur in ways the software doesn’t know how to test or can’t. This is especially true of memory when problematic sections are outside the testable range but still used by the system.