New
#11
Confirm the following at least before attempting what others are suggesting:
If you are using Windows 7 Home BASIC version of Windows 7 installed on your PC it will only address 4GBof physical RAM. You are going to have to upgrade to Windows 7 Home Premium which I think will address either upto 8 or 12 GB of RAM.
The other possibility if you have WIndows 7 Home Premium is that you may have the 32-bit version of Windows 7 installed instead of teh 64-bit version. Check which version was installed on your PC.
BTW - you get both the 32-bit and 64-bit discs with Windows 7 Home Premium and greater. Perhaps you just grabbed the wrong disc out of teh package when you did the install.