How to force Windows 7 to use the entire available RAM

It is a little known fact that Windows 7 doesn’t use the entire available RAM by default. For example if you have 8GB of RAM and a 64-bit Windows 7, it will use around 7.1GB of it (in the case of 4GB of RAM and 32-bit Windows 7, it will use around 3.5GB). The reason [...]