The big advantage of vista 64 is it can address large of memory to itself, well from what i read vista can address up to 128 GB RAM . But once you install vista 64, the cpu is locked to 64bit processing only (well most desktop cpu out there is not real 64 btw) which mean you can't use 32 bit native applications without compatibility support.



Actually it depends, on other part of the PC as well. Vista don't address the memory from RAM only, other component as video cards, etc also play role. Therefore if you got 512 mb of video card memory Vista will have to use 512MB of that address space to address your video memory to itself, which therefore vista address your ram lower. But it never hurt to use 4 GB of ram for 32 bit vista but just your Vista will not enough space to address it.

Well, 4GB minus the address space required by addin cards and other hardware equals the MAXIMUM addressable Vista RAM. Source http://www.vistaclues.com/reader-question-...-windows-vista/

This post has been edited by takercena: Dec 28 2008, 07:39 PM