Ed from FL writes:
I have an HP p6210f Quad Core (Win 7) with 6 GB of memory installed, however, in looking at the System Info it says I have “Installed Memory 6GB (2 GB Usable). The memory checks good, I swapped slots – no change. I do not think there is a setting to correct this, is there? Maybe it’s the MB and/or CPU?
This could either be just confusion over what the system is showing you or an actual problem you’ll need to fix, so I’ll go over both options.
The first step is to right click on the task bar and click Task Manager. Go to the performance tab and look on Physical Memory (MB) and see what it says. If this shows Total 6000 (or about), then you are fine and what you’re seeing is the memory being used by your operating system in normal daily usage. The Available number is the important number and is what programs have left over to use after the current programs/items are loaded. Windows will manage your memory to optimize caching as you load and access programs, so this number will change.
If the Total Memory shows as 2048 GB, there may be a startup setting that has been altered, forcing Windows to use only 2 GB of memory instead of the maximum available. You can edit this boot option by first opening msconfig by holding down Windows Key and the letter R (or going to Start then Run) and typing msconfig, and pressing enter.
In msconfig, click on the boot tab then click on Advanced options. Make sure the Maximum memory checkbox is unchecked. If it is checked (most likely if Windows is not showing the full installed memory) then uncheck the box, press OK and reboot your computer. When your computer restarts you should now have the full installed memory available for use by windows.