There will come a time when you think your RAM is playing up or perhaps it is new and you want to make sure everything is all OK before you continue to setup your Custom PC. Testing your RAM can help diagnose Operating system lockups, crashes, strange behaviour and explain why your CPU will not hit the magic 4GHz when overclocking.

Thankfully it is very easy to test your RAM, and here is how;

1 – Download a program called Memtest86 available from Alternatively, for ease of use you can download the 5.01 files directly from us;

CD Version V5.01 zip

USB Stick Version V5.01 zip

2 – We are going to use a CD version of the program as everyone has a CD drive so make sure you download the latest “Pre Compiled Bootable ISO”. It does not matter whether you go for the .gz or .zip version, just make sure you have a program that will open .gz or .zip files. The latest versions of Microsoft Windows (7 onwards) has a zip reader built in, so we recommend you download the .zip version for ease of use.

3 – Once you have your file, unzip it and you should be left with a file that looks like memtest86+-XXX.iso. The 3 X’s represent the version number of the program. For example if you have downloaded version 5.01 then your file will look like memtest86+-5.01.iso.

4 – The *.iso file is what is known as an image file, at this stage this is no good to us, we need it on a CD. Use your favourite CD/DVD burning software to burn the file as an image. If you are using a modern Microsoft Windows operating system then again it has its own built in software for doing this, simply double click the *.iso file and it will open the Windows Disk Image Burner. Insert your blank CD and click Burn.

If you have installed another CD/DVD burning software and want to use the built in Windows Disk Image Burner then right click your *.iso file and select open with and then Windows Disk Image Burner.

5 – After a few minutes your CD will finish burning, you now have a bootable and usable Memtest86+ disk!

6 – Should you wish to use the USB version, simply download the USB version, unzip and run the *.exe installer and follow the simple prompts. Within seconds you will have a bootable USB version.

7 – Reboot your PC, whilst making sure your bootable Memtest86+ disk is in your CD/DVD Drive, and boot from it. It will immediately load up with Memtest86+. This should also be the case if you are using the USB version in a USB port. If your operating system loads then you will need to change your boot order in the BIOS.

You will see a blue screen with lots of numbers. The bits you are interested in are;

Time – How long memtest has been running.

Pass – How many full tests have been carried out.

Errors – How many errors have been found.

To correctly test your RAM you need to let this test run for at least 24 hours, ideally 48 if possible. Ultimately you want to run 20 rests/passes to fully test the RAM. If you are investigating a issue it is important that you do allow the time to let it complete 20 passes. If your RAM is all OK, not much will change. The timer and the number of passes will go up but the reported fault number will stay at 0.

If your RAM is possibly faulty, your error number will be 1 or greater, and you will be presented with red horizontal strips of information along the bottom. It is however worth noting that is only one error is present, it does not necessarily mean the RAM is faulty (its to do with the way memtest works). When RAM is faulty 99% of the time you will get multiple errors quite often hundreds or thousands in the first few minutes of testing, if this is the case you can strongly point your finger at the RAM not being right and stop the test as it will only continue to pump out more errors.

If no errors have been found after 20 passes, congratulations, your RAM in your Custom PC is perfect.