Quote - XP32 have no idea of what is a 64 bit CPU and any memory above 4GB would be ignored, so I can make my own memory manager for accesing the memory above 4GB leaving the lower 4GB for Windows and normal memory access. My program will be able to use and abuse of the upper memory and Windows XP will have no idea that I am using this memory, so it will not disturb my memory and my memory will be under my own control.

 

I don't see how that is valuable over designing your app to be fully 64-bit aware and simply running under a 64-bit OS, as all memory management would be handled by the operating system and thus would save you TREMENDOUS amounts of work, but if you really want to know how, here's one interesting workaround for the 2gb process limit:

http://blogs.msdn.com/oldnewthing/archive/2004/08/10/211890.aspx

A funny top-down observation by Raymond Chen (same guy)
http://blogs.msdn.com/oldnewthing/archive/2007/03/01/1775759.aspx

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