|A 32 bit client OS has a physical address space of 4 GB. But this must be shared with RAM and memory mapped hardware devices. Since RAM and hardware cannot shore the same addresses and hardware must have priority you will inevitably loose access to some RAM. Typically 3 to 3.5 GB will be accessible but it can be less. If RAM is shared with a video card this will be further reduced.|
With a 32 bit client OS there is no solution to this.