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