That is not the advantage of x64 platform it can handle HUGE amount, very more than the small 4GB about 2^63 bytes of memory however nos OS has support for that amt. (xp x64 support upto 128GB of memory only) so if u build x64 app, u can see the diff. b/w having able to use full 4GB (x86 app) and 128GB (under x64 xp , & may more in linux)