|I've never used the desktop i945 chipset, but the mobile i945 chipsets will only do up to 3GB of RAM. The desktop 945 probably has the same limitation. |
AFAIK, not even a BIOS update can solve this, as the problem lies in the fact that the memory controller component of the i945 can only handle 32-bit memory access.
I currently have 4GB of RAM installed in my i945-based laptop, but Windows Vista Business 64 only sees 3GB of it.