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Windows only sees 4 GB of memory:

alt text

And yet 6 GB are installed:

alt text

Why? What can I do to troubleshoot the problem?


  • Motherboard: ASUS P7P55D
  • Video card: Radeon HD 4890
  • Power Supply: 630W
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What is you System Specs? Motherboard, Power supply, video cards, etc.? – KronoS Sep 1 '10 at 16:30

you need to refresh you windows experience index. Try that, and see if it updates.

You can also see if the task manger is showing the correct amount memory.

Prese Ctrl+Shift+Esc and the task bar will be brought up. Select the properties tab and then look to see if the correct amount of memory is being displayed.


There are two things that seem to prevent Windows from seeing the full amount of memory of the system. The first is when Windows has somehow limited the amount of memory to be used. To check this:

  • Open msconfig (press the windows key, type in msconfig and then enter) and go to the boot tab.

  • Click the advanced tab and make sure that the maximum memory box is unchecked

The other thing that can cause this issue is a lack of power from the power supply. If you a dignificant amount of ram, multiple video cards, or even just one high end GPU, a high end CPU, mulitple hard drives, then a power supply must be a higher end supply. Here is a website that easily calculates what wattage you need for the PC setup you have.

You can also disconnect any unnecessary components of the PC (i.e. Optical Drive; spare hard drives; USB drives; etc.) and then boot the system and see if Windows recognizes the rest of the memory.

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The windows experience index is completely unrelated... – Andreas Bonini Sep 1 '10 at 16:00
I agree with KronoS "Your Windows Experience Index needs to be refreshed". I know this because it says so in your helpful screenshot. :) – Brian Ensink Sep 1 '10 at 16:03
@Andreas Bonini Yes it does if you look at your memory through the Windows System overview. I bet if you pulled up task manager and looked at the performance tab you'll see all 6 gigs there. – KronoS Sep 1 '10 at 16:17
Yes, the Windows Experience Index is just an optional tool for Windows that allows you to measure the performance. It has nothing to do with how much memory windows sees :\ The power supply is fine, and the maximum memory box is unchecked. – Andreas Bonini Sep 1 '10 at 17:33
@KronoS: if the power supply isn't powerful enough, 2 GB of memory being ignored is not a symptom. Also there is no way it uses any amount near that with the video card and CPU in idle. – Andreas Bonini Sep 1 '10 at 21:26

I would update your system BIOS if an update is possible/available. The same thing happened to me on my Thinkpad W510.

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