Why can my Windows 7 32-bit only use 2.3GB of RAM?

I have 4GB of RAM installed. According to the "System" section of the control panel, 2.3 GB of the 4 GB is usable.

I tried adjusting msconfig.exe, but it made no difference. I changed the "dedicated graphic memory" from 128 to 64 MB in my BIOS, now my system can use 2.36 GB of RAM. Shouldn't Windows 7 32-bit be able to use 3-3.5 GB of RAM?

I'm using an Acer Travelmate 8572 laptop.

Edit: Could it be because of my Intel HD Graphics?

Solution 1:

Of course, a 32-bit OS can only address 4GB, but that does not mean that happens in practice.

Many of those addresses are used up by the video memory, and other motherboard components. Check out footnotes 3 + 6 on this document about your system:

http://support.acer.com/acerpanam/notebook/2010/Acer/TravelMate/TravelMate8572/TravelMate8572sp2.shtml

Your system tops out at 3GB, minus the video memory. You will need a 64-bit OS to address more.