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Windows Doesn't Use Full RAM

Arsen Karapetyan

RAM is a very important components in your PC. What if Windows does't user your full RAM. Here is a solutions to your issue.

Why Won't Windows Use Full RAM?

There are four reasons why your Windows won't use full RAM:

  1. The RAM that you bought is not compatible with your motherboard
  2. Your BIOS is not up-to-date to support your RAM
  3. The copy of your Windows does not support the amount of RAM that you have.
  4. Your Windows is not set up correctly

RAM is Not Compatible with Motherboard

Is it very possible that the manufacturere of your computer motherboard did not make your specific RAM modules compatible with the featureset that came with your motherboard.

A good example would be a different generation of RAM. Say, you bought DDR4 RAM and your motherboard only supports DDR3. You will have to get a new RAM module. Alternatively, you can change the motherboard. The frist option is probably going to cost you less.

If you are stuck with the old motherboard, see what to do if your Windows suddenly feels very slow.

Also, here's why your RAM migh be running at a lower than advertised speed.

BIOS is Not Up To Date

Sometimes the motherboard manufacturer rushes the board out and does not include support for all RAM modules. This way, you might have a DDR4 RAM module, and it might not be compatible with your DDR4 supporting motherboard.

Sometimes, certain RAM timings or frequencies are not supported as well.

To fix it, go to your motherboard's manufacturere's web site and search for an updated BIOS. Here is an example on ASUS's web site.

Windows Doesn't Support Large RAM

Windows XP, Windows 7, Windows Vista, Windows 10 all have restrictions on the amount of RAM you can have with a certain license. Say, a 32-Bit version of Windows 10 Home supports a maximum addressable of RAM of 4GB. Here is a fully supported amount of RAM in different Windows 10 versions:

Windows 10 Home 32-Bit4GB
Windows 10 Home 64-Bit128GB
Windows 10 Pro 32-Bit4GB
Windows 10 Pro 64-Bit2TB
Windows 10 versions maximum RAM support

Here, you'd have to updgrade your Windows 10 license. There is no way around it. If you have a 32-Bit version of Windows 10, you will have to reinstall your entire Windows 10. Even if you bought a new 64-Bit license.

If you are still using Windows 7, see why you should upgrade to Windows 10 or how to get Windows 10 free (sort of).

Your Windows RAM Settings are Not Set Up Correctly

It is very unlikely, but plausible that your Windows is not correctly set up to support to detect all of your RAM. If your Windows is not detecting full RAM, try the following trick. Watch the video below.

Windows Not Detecting Full RAM

Remember, do this at your own risk and please enter the right amout of RAM in the box. Otherwise your Windows will not load and your will get a blue screen of death.

If you can boot into Windows and you occasionally get a BSD, try this fix that shows you how to fix a blue screen of death in Windows.