Really i can show you a x86 system using 128GB of RAM if you want. It isnt hard to photoshop a image. PAE doesnt allow for the system to use that much RAM. 32 Bit can't use more than 4GB. It is the physical limitation of the coding of the software. It is even stated as much by Microsoft now.
Vista and Win7 will both tell you on the system properties screen now that you have 4GB of RAM (3GB usable).
So you dont have to believe me. But ask any programmer. Anyone who knows about the physical limitations. The part on the first page from Computer Guru, is coming directly from a programmer for Microsoft and Windows.