[Anwsered] 12GB RAM installed, 8GB usable.

12GB RAM installed, 8GB usable.

Apologies if this has been asked before but I haven't been able to find a good answer.  In system settings, it has been displaying

Installed Memory: 12.00GB (8.00GB Usable)
I've unchecked maximum memory in MSCONFIG boot and checked my BIOS. 
For a while it showed all 12 were usable so I'm doubting it's a hardware problem.
Thoughts?

Keys to the Problem 12GB RAM installed, 8GB usable.

Download SmartPCFixer to Fix It (Free)

Hi,
I would suggest you to refer the link below and check if it helps.
http://support.microsoft.com/kb/978610
 
Hope this information is helpful.

Manually editing the Windows registry to fix Error 12GB RAM installed, 8GB usable.

Caution: Unless you an advanced computer user, we DO NOT recommend editing the Windows registry manually. Using Registry Editor incorrectly can cause serious problems that may require you to reinstall Windows. We do not guarantee that problems resulting from the incorrect use of Registry Editor can be solved. Use Registry Editor at your own risk.

• Click the Start button.
• Type "command" in the search box... DO NOT hit ENTER yet!
• While holding CTRL-Shift on your keyboard, hit ENTER.
• You will be prompted with a permission dialog box.
• Click Yes.
• A black box will open with a blinking cursor.
• Type "regedit" and hit ENTER.
• In the Registry Editor, select the Error 0x9C-related key (eg. Windows Operating System) you want to back up.
• From the File menu, choose Export.
• In the Save In list, select the folder where you want to save the Windows Operating System backup key.
• In the File Name box, type a name for your backup file, such as "Windows Operating System Backup".
• In the Export Range box, be sure that "Selected branch" is selected.
• Click Save.
• The file is then saved with a .reg file extension.
• You now have a backup of your MACHINE_CHECK_EXCEPTION-related registry entry.

Recommended Method to Fix the Problem: 12GB RAM installed, 8GB usable.:

How to Fix 12GB RAM installed, 8GB usable. with SmartPCFixer?

1. Click the button to download SmartPCFixer . Install it on your system.  Open it, and it will scan your system. The junk files will be shown in the list.

2. After the scan is done, you can see the errors and problems which need to be repaired.

3. When the Fixing part is finished, your computer has been speeded up and the errors have been fixed

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