Windows 7 using exactly HALF the installed memory

memorywindows 7

I've taken this directly from system information:

  • Installed Physical Memory (RAM) 4.00 GB
  • Total Physical Memory 2.00 GB
  • Available Physical Memory 434 MB
  • Total Virtual Memory 5.10 GB
  • Available Virtual Memory 1.19 GB
  • Page File Space 3.11 GB

Also the BIOS reports a full 4GB available.

Note the 4gb installed, yet 2gb total. I understand that on a 32 bit operating system, you'll never get the full 4gb of ram, however typically you'll get in the range of 2.5-3.2gb of ram.

I have only 2gb available! My swap file goes nuts when I do anything! Note that I have dual SLI nvidia video cards, each with 512mb of on board ram, though I have the SLI feature turned off.

Anybody know why Windows might claim that I have exactly 2gb of ram total?

Note: previously asked on serverfault, but closed as "belongs on superuser" before this site opened: https://serverfault.com/questions/39603/windows-7-using-exactly-half-the-installed-memory (I still need an answer!)

Best Answer

First of you will lose very much of your available memory with two graphic cards, that's 1GB of RAM lost right there plus the other devices.

There is a switch you can check in msconfig. Go to start, type msconfig and hit enter. Go to the boot tab, click advanced options. Check if the Max Memory option is enabled, if it is then disable it and reboot.

Edit:

The issue is with something called address space. On a 32-bit system you have 4GB of address space and all devices you need to use have to be mapped into the address space. Each device that gets mapped in will carve out a bit of the address space and render it unusable for the rest of the system.

The only way to get more than 2.5-3GB of usable memory in Windows is to install the 64-bit version. After that is installed it will look the same with only 2GB of memory usable. To get all available memory you need to go into BIOS and enable an option called memory remap.

The memory remap features moves all the mapped devices above the 4GB limit in the address space thus freeing up your address space for use by the system.

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