Windows 7 Installed Memory Problem


Oct 31, 2011
I've just bought 2 sticks (2x 2GB) of Kingston DDR2-PC6400 DIMM modules for my Shuttle SG33G5 to upgrade it to a total of 4GB of RAM.

However, under the resource monitor, Windows 7 reports "Installed RAM: 3.24GB", " I've read lots of other posts saying that their computer reports "4GB installed ram, 3.24gb usable", but mine just says 3.24GB installed and mentions nothing about "Usable". I am using onboard VGA graphics, but the BIOS is set to use 128MB for that which does not account for the difference. Anyhow, surely this would affect the usable amount, not the installed amount of RAM?

If I run msinfo32.exe, the installed ram value says "not available". If I run CPU-Z, it tells me the installed memory is 4GB, but I have a feeling that might just querying the RAM chips themselves which would report what they should be providing as per their model number, but not necessarily what they are providing to the PC. I've swapped the modules around to no avail, run Windows Memory Diagnostics which found no faults. I even replaced the two old modules (2GB total) and they report (1.99GB installed) which is correct, so now I am suspicious about a faulty RAM module that functions normally as RAM, but just doesn't provide it's full amount. Is a fault like this possible?

Any help would be greatly appreciated.