How to enable 4GB in my Windows 7 64 bit?
I have 4GB of installed RAM and a 64 bit OS. However, both the system properties and the resource monitor say that only 3GB are usable:
I've read that it could be a motherboard issue and that Memory mapping should be enabled in the BIOS. I checked and it's indeed enabled. I also checked the manufacturer's page (it's an Asus M2N-MX SE Plus) and it says that it supports up to 4GB of memory.
I think the culprit here is the video card: I have a Nvidia Geforce 8400 GS, and dxdiag says it has 1521 MB of memory, which is precisely the card's memory (512 MB) plus the gigabyte I'm missing from RAM.
Is that right, and how can I solve this issue and give that 1GB back to Windows?