32-bit CPU can address 4G but 32-bit Windows needs to use some of the address space for purposes other than main memory such as GPU etc.
With a 64-bit CPU and Windows, address space is not an issue but it could be that a large chunk of memory is configured to be assigned for the integrated GPU. This can be adjusted in BIOS.
Last edited by unmesh; Nov 6, 2016 at 10:24 am