The table in this article is well done and may be of assistance:
http://www.mydigitallife.info/2008/0...windows-vista/

Notice there are no speed increases by switching to x64.
Additionally, if you have less than 4GB RAM and switch to x64, you _may_
actually experience a performance degradation.


"Jude Alvia" <guest@unknown-email.com> wrote in message
news:a56c1ae7d5c9b8b4d127095e3f54cc12@nntp-gateway.com...
>
> Currently have a pc with oem vista ultimate 32bit. I have a retail
> version of vista ultimate and trying to decide what version of vista
> (64bit or 32bit) to install on a totally new (just built) computer. Very
> pleased with performance of my vista 32bit computer but the new one is
> going to be my toy. Any suggestions or opinions are appreciated. Is
> there any reason I wouldn't be able to install vista 32bit now and then
> later install 64bit later on down the road (like when it has more
> compatibility with programs)?
>
> Thanks in advance for input.
>
>
> --
> Jude Alvia