New
#11
A few comments here. I'll assume at this point that hardware problems are ruled out.
32 bits client versions of Windows arbitrarily restricts memory to 4GB, regardless of how much you actually have. An on-board graphics card is a typical reason for that, and if that's the case nothing will "recover" that memory (it would be used by the GPU, not wasted but not at the OS's disposal).
But if you have a dedicated GPU, then upgrading to a 64 bits Windows would recover those and get the full 4GB. The memory in 32 bits Windows is effectively wasted there (for a different combination of causes).