Are you using a 32-bit windows operating system? 32-bit windows can only use approx 3.7GB of RAM. You will need a 64-bit operating system to be able to address the extra 0.3GB which the motherboard can remap above the 4GB limit. Microsoft crippled the PAE (physical address extensions) of 32-bit windows on purpose. So even if the graphics card you installed freed the RAM occupied by the integrated GPU, the 32-bit windows can't use it.