If you have PAE on on a 32bit system running a 64bit capable CPU then wile what windows can see and report is 4gb less the memory address space of the graphics card & page file, however large address aware programs and applications can use ram >4gb independently & regardless of what windows reports to them.
When I used 32bit XP with PAE on with my i7 CPU some of the application I used could see and use all my 6gb of ram plus any amount of page file which they wouldn’t do if PAE was off or a 32bit CPU was used, simpaly becouse they were 32bit large address aware programs with a 64bit CPU on a 32bit OS.
